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  • Convert array of hashes to array of structs?

    - by keruilin
    Let's say I have two objects: User and Race. User has two attributes: first_name, last_name. And Race has three attributes: course, start_time, end_time. Now let's say I create an array of hashes like this: user_races = races.map{ |race| {:user = race.user, :race = race} } How do I then convert user_races into an array of structs, keeping in mind that I want to be able to access the attributes of both user and race from the struct element?

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  • Problem in searching String array [on hold]

    - by user2573607
    I'm working on a bank interface project, where I have to search an array of string when the user types in his username. The array has 10 strings, but only the first string is recognized as a valid username...I'm positive that the syntax of the search technique(Linear Search) is correct, but I cannot seem to find the problem. The code however compiles properly. Any answer will be appreciated, TIA! Aparna

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  • multi-dimension array value sorting in php

    - by David
    Another potentially interesting (or n00b, whatever comes first) question. I am building up an array with a set of database fields with information about table, actual field name and descriptive field name as a multi-dimensional array. Here is what it currently looks like: $Fields['User']['ID'] = "User ID"; $Fields['User']['FirstName'] = "First Name"; $Fields['Stats']['FavouriteOrder'] = "Favourite Item Ordered"; $Fields['Geographic']['Location'] = "Current Location"; $Fields['Geographic']['LocationCode'] = "Current Location Code"; Okay, this is fine, but I am piping this into a system that allows exporting of selected fields, and in the end I want to foreach() through the different levels, extract the data and then ultimately have all the descriptive fields to be displayed sorted alphabetically using their descriptive name. So ultimately in the order: Current Location, Current Location Code, Favourite Item Ordered, First Name then User ID - obviously keeping index associations. I can't use usort() and I can't use array_multisort()... or maybe I can and I just don't know how. usort() seems to need a key to sort by, but I have variable keys. array_multisort() just seems to do the same as sort() really. Any ideas?

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  • how to change type of value in an php array and sorting it..is it possible ?

    - by justjoe
    hi, i got problem with my code and hopefully someone able to figure it out. The main purpose is to sort array based on its value (then reindex its numerical key). i got this sample of filename : $filename = array("index 198.php", "index 192.php", "index 144.php", "index 2.php", "index 1.php", "index 100.php", "index 111.php"); $alloutput = array(); //all of index in array foreach ($filename as $name) { preg_match('#(\d+)#', $name, $output); // take only the numerical from file name array_shift($output); // cleaned. the last code create duplicate numerical in $output, if (is_array($hasilku)) { $alloutput = array_merge($alloutput, $output); } } //try to check the type of every value in array foreach ($alloutput as $output) { if (is_array($hasil)) { echo "array true </br>"; } elseif (is_int($hasil)) { echo "integer true </br>"; } elseif (is_string($hasil)) { //the numerical taken from filename always resuld "string". echo "string true </br>"; } } the output of this code will be : Array ( [0] = 198 [1] = 192 [2] = 144 [3] = 2 [4] = 1 [5] = 100 [6] = 111 ) i have test every output in array. It's all string (and not numerical), So the question is how to change this string to integer, so i can sort it from the lowest into the highest number ? the main purpose of this code is how to output array where it had been sort from lowest to highest ?

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  • How to handle key in PhP array if the key contains japanese characters [migrated]

    - by Jim Thio
    I have this array: [ID] => ????????-???????????__35.79_139.72 [Email] => [InBuildingAddress] => [Price] => [Street] => [Title] => ???????? ??????????? [Website] => [Zip] => [Rating Star] => 0 [Rating Weight] => 0 [Latitude] => 35.7865334803033 [Longitude] => 139.716800710514 [Building] => [City] => Unknown_Japan [OpeningHour] => [TimeStamp] => 0000-00-00 00:00:00 [CountViews] => 0 Then I do something like this: $output[$info['ID']]=$info; //mess up here $tes=$info['ID']['Title']; Well guess what it messes up. Basically even though the content of an array in PhP can be Japanese. Is this true? What's wrong. The error I got is: Debug Warning: /sdfdsfdf/api/test2.php line 36 - Cannot find element ????????-???????????__35.79_139.72 in variable Debug Warning: /sdfdsfdf/api/test2.php line 36 - main() [function.main]: It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Asia/Krasnoyarsk' for '7.0/no DST' instead So many question mark Why is this happening. What's really going on inside PhP? Where can I learn more of such things. Most importantly, what would be the best way to handle this situation. Should I tell PhP to internally always use UTF-8? Does PhP array inherenty cannot use non ascii id?

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  • Sorting a 2D array in obj-c?

    - by Debashis
    I have a 2D array as follows: [[@"string value", @"string value", NSInteger], [@"string value", @"string value", NSInteger], [@"string value", @"string value", NSInteger]] How would I sort the second dimension of arrays by the NSInteger?

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  • best way to get a vector from sparse matrix

    - by niko
    Hi, I have a m x n matrix where each row consists of zeros and same values for each row. an example would be: M = -0.6 1.8 -2.3 0 0 0; 0 0 0 3.4 -3.8 -4.3; -0.6 0 0 3.4 0 0 In this example the first column consists of 0s and -0.6, second 0 and 1.8, third -2.3 and so on. In such case I would like to reduce m to 1 (get a vector from a given matrix) so in this example a vector would be (-0.6 1.8 -2.3 3.4 -3.8 -4.3) Does anyone know what is the best way to get a vector from such matrix? Thank you!

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  • Efficiently solving sparse matrices

    - by anon
    For solving spare matrices, in general, how big does the matrix have to be (as a rule of thumb) for methods like congraduate descent to be faster than brute force solvers (that do not take advantage o sparsity)?

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  • Convert char array to int array c++

    - by Yadira Suazo
    I`m having problems converting a char array read from file to an int array. Maybe someone can help me. This is my code: char vectorPatron[67]; int iPatrones[67]; archivo = fopen("1_0.txt", "r"); for(i=0;i<67;i++){ fscanf(archivo, "%c", &vectorPatron[i]); printf("%c",vectorPatron[i]); } fclose(archivo); for(i=0;i<67;i++){ iPatrones[i] = atoi(&vectorPatron[i]); printf("%d",iPatrones[i]); }

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  • Android java assigning 2d array to 3d array

    - by semajhan
    I'm running into problems trying to assign a 2d array to a 3d array, so I thought i'd ask a question about 3d and 2d arrays. Say I have a masterArray[][][] and wanted to put childArray1[][] and childArray2[][] into it. This is how I have done it and was wondering if that is the correct way of applying it: private int[][][] masterArray; private int[][] childArray1 = { {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 0, 0, 1, 0, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 0, 1, 1, 1, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 1, 1, 0, 1}, {1, 0, 1, 1, 0, 1, 8, 1, 0, 1}, {1, 0, 7, 1, 1, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 0, 1, 0, 1}, {1, 0, 1, 1, 1, 1, 1, 1, 0, 1}, {1, 0, 0, 0, 0, 0, 0, 9, 0, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1} }; private int[][] childArray2 = { {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {0, 0, 0, 0, 0, 0, 0, 0, 1, 1}, {1, 1, 1, 1, 7, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 0, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 0, 0, 0, 1, 1, 1}, {1, 1, 1, 9, 1, 1, 8, 0, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, }; Ok, so in my init method I use these some methods to set the child arrays into the master array. What I was curious about was how this exactly works. I assumed the following: masterLevel = new int[MAX_LEVELS][MAP_WIDTH][MAP_HEIGHT]; for (int x = 0; x < MAP_WIDTH; x++) { for (int y = 0; y < MAP_HEIGHT; y++) { masterArray[currentLevel][x][y] = childArray1[x][y]; } } Would that work? In my application things aren't working so I picking out code that I am not 100% sure on.

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  • Reverse subarray of an array with O(1)

    - by Babibu
    I have an idea how to implement sub array reverse with O(1), not including precalculation such as reading the input. I will have many reverse operations, and I can't use the trivial solution of O(N). Edit: To be more clear I want to build data structure behind the array with access layer that knows about reversing requests and inverts the indexing logic as necessary when someone wants to iterate over the array. Edit 2: The data structure will only be used for iterations I been reading this and this and even this questions but they aren't helping. There are 3 cases that need to be taking care of: Regular reverse operation Reverse that including reversed area Intersection between reverse and part of other reversed area in the array Here is my implementation for the first two parts, I will need your help with the last one. This is the rule class: class Rule { public int startingIndex; public int weight; } It is used in my basic data structure City: public class City { Rule rule; private static AtomicInteger _counter = new AtomicInteger(-1); public final int id = _counter.incrementAndGet(); @Override public String toString() { return "" + id; } } This is the main class: public class CitiesList implements Iterable<City>, Iterator<City> { private int position; private int direction = 1; private ArrayList<City> cities; private ArrayDeque<City> citiesQeque = new ArrayDeque<>(); private LinkedList<Rule> rulesQeque = new LinkedList<>(); public void init(ArrayList<City> cities) { this.cities = cities; } public void swap(int index1, int index2){ Rule rule = new Rule(); rule.weight = Math.abs(index2 - index1); cities.get(index1).rule = rule; cities.get(index2 + 1).rule = rule; } @Override public void remove() { throw new IllegalStateException("Not implemented"); } @Override public City next() { City city = cities.get(position); if (citiesQeque.peek() == city){ citiesQeque.pop(); changeDirection(); position += (city.rule.weight + 1) * direction; city = cities.get(position); } if(city.rule != null){ if(city.rule != rulesQeque.peekLast()){ rulesQeque.add(city.rule); position += city.rule.weight * direction; changeDirection(); citiesQeque.push(city); } else{ rulesQeque.removeLast(); position += direction; } } else{ position += direction; } return city; } private void changeDirection() { direction *= -1; } @Override public boolean hasNext() { return position < cities.size(); } @Override public Iterator<City> iterator() { position = 0; return this; } } And here is a sample program: public static void main(String[] args) { ArrayList<City> list = new ArrayList<>(); for(int i = 0 ; i < 20; i++){ list.add(new City()); } CitiesList citiesList = new CitiesList(); citiesList.init(list); for (City city : citiesList) { System.out.print(city + " "); } System.out.println("\n******************"); citiesList.swap(4, 8); for (City city : citiesList) { System.out.print(city + " "); } System.out.println("\n******************"); citiesList.swap(2, 15); for (City city : citiesList) { System.out.print(city + " "); } } How do I handle reverse intersections?

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  • Array filteration PHP

    - by Muhammad Sajid
    I have an array with values like: Array ( [0] => Array ( [parent] => Basic [parentId] => 1 [child] => Birthday [childId] => 2 ) [1] => Array ( [parent] => Basic [parentId] => 1 [child] => Gender [childId] => 3 ) [2] => Array ( [parent] => Geo [parentId] => 10 [child] => Current City [childId] => 11 ) [3] => Array ( [parent] => Known me [parentId] => 5 [child] => My personality [childId] => 7 ) [4] => Array ( [parent] => Known me [parentId] => 5 [child] => Best life moment [childId] => 8 ) ) And I want to filter this array such that their filtration based on parent index, and the final result would be like: Array ( [0] => Array ( [parent] => Basic [parentId] => 1 [child] => Array ( [0] => Birthday [1] => Gender ) ) [1] => Array ( [parent] => Geo [parentId] => 10 [child] => Array ( [0] => Current City ) ) [2] => Array ( [parent] => Known me [parentId] => 5 [child] => Array ( [0] => My personality [1] => Best life moment ) ) ) For that I coded : $filter = array(); $f = 0; for ($i=0; $i<count($menuArray); $i++) { $c = 0; for( $b = 0; $b < count($filter); $b++ ){ if( $filter[$b]['parent'] == $menuArray[$i]['parent'] ){ $c++; } } if ($c == 0) { $filter[$f]['parent'] = $menuArray[$i]['parent']; $filter[$f]['parentId'] = $menuArray[$i]['parentId']; $filter[$f]['child'][] = $menuArray[$i]['child']; $f++; } } But it results : Array ( [0] => Array ( [parent] => Basic [parentId] => 1 [child] => Array ( [0] => Birthday ) ) [1] => Array ( [parent] => Geo [parentId] => 10 [child] => Array ( [0] => Current City ) ) [2] => Array ( [parent] => Known me [parentId] => 5 [child] => Array ( [0] => My personality ) ) ) Could anyone point out my missing LOC?

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  • 3D array in a 2D array

    - by Smallbro
    Currently I've been using a 3D array for my tiles in a 2D world but the 3D side comes in when moving down into caves and whatnot. Now this is not memory efficient and I switched over to a 2D array and can now have much larger maps. The only issue I'm having now is that it seems that my tiles cannot occupy the same space as a tile on the same z level. My current structure means that each block has its own z variable. This is what it used to look like: map.blockData[x][y][z] = new Block(); however now it works like this map.blockData[x][y] = new Block(z); I'm not sure why but if I decide to use the same space on say the floor below it wont allow me to. Does anyone have any ideas on how I can add a z-axis to my 2D array? I'm using java but I reckon the concept carries across different languages.

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  • [C++] A minimalistic smart array (container) class template

    - by legends2k
    I've written a (array) container class template (lets call it smart array) for using it in the BREW platform (which doesn't allow many C++ constructs like STD library, exceptions, etc. It has a very minimal C++ runtime support); while writing this my friend said that something like this already exists in Boost called MultiArray, I tried it but the ARM compiler (RVCT) cries with 100s of errors. I've not seen Boost.MultiArray's source, I've just started learning template only lately; template meta programming interests me a lot, although am not sure if this is strictly one, which can be categorised thus. So I want all my fellow C++ aficionados to review it ~ point out flaws, potential bugs, suggestions, optimisations, etc.; somthing like "you've not written your own Big Three which might lead to...". Possibly any criticism that'll help me improve this class and thereby my C++ skills. smart_array.h #include <vector> using std::vector; template <typename T, size_t N> class smart_array { vector < smart_array<T, N - 1> > vec; public: explicit smart_array(vector <size_t> &dimensions) { assert(N == dimensions.size()); vector <size_t>::iterator it = ++dimensions.begin(); vector <size_t> dimensions_remaining(it, dimensions.end()); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimensions[0], temp_smart_array); } explicit smart_array(size_t dimension_1 = 1, ...) { static_assert(N > 0, "Error: smart_array expects 1 or more dimension(s)"); assert(dimension_1 > 1); va_list dim_list; vector <size_t> dimensions_remaining(N - 1); va_start(dim_list, dimension_1); for(size_t i = 0; i < N - 1; ++i) { size_t dimension_n = va_arg(dim_list, size_t); assert(dimension_n > 0); dimensions_remaining[i] = dimension_n; } va_end(dim_list); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimension_1, temp_smart_array); } smart_array<T, N - 1>& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() const { return vec.size(); } }; template<typename T> class smart_array<T, 1> { vector <T> vec; public: explicit smart_array(vector <size_t> &dimension) : vec(dimension[0]) { assert(dimension[0] > 0); } explicit smart_array(size_t dimension_1 = 1) : vec(dimension_1) { assert(dimension_1 > 0); } T& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() { return vec.size(); } }; Sample Usage: #include <iostream> using std::cout; using std::endl; int main() { // testing 1 dimension smart_array <int, 1> x(3); x[0] = 0, x[1] = 1, x[2] = 2; cout << "x.length(): " << x.length() << endl; // testing 2 dimensions smart_array <float, 2> y(2, 3); y[0][0] = y[0][1] = y[0][2] = 0; y[1][0] = y[1][1] = y[1][2] = 1; cout << "y.length(): " << y.length() << endl; cout << "y[0].length(): " << y[0].length() << endl; // testing 3 dimensions smart_array <char, 3> z(2, 4, 5); cout << "z.length(): " << z.length() << endl; cout << "z[0].length(): " << z[0].length() << endl; cout << "z[0][0].length(): " << z[0][0].length() << endl; z[0][0][4] = 'c'; cout << z[0][0][4] << endl; // testing 4 dimensions smart_array <bool, 4> r(2, 3, 4, 5); cout << "z.length(): " << r.length() << endl; cout << "z[0].length(): " << r[0].length() << endl; cout << "z[0][0].length(): " << r[0][0].length() << endl; cout << "z[0][0][0].length(): " << r[0][0][0].length() << endl; // testing copy constructor smart_array <float, 2> copy_y(y); cout << "copy_y.length(): " << copy_y.length() << endl; cout << "copy_x[0].length(): " << copy_y[0].length() << endl; cout << copy_y[0][0] << "\t" << copy_y[1][0] << "\t" << copy_y[0][1] << "\t" << copy_y[1][1] << "\t" << copy_y[0][2] << "\t" << copy_y[1][2] << endl; return 0; }

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  • A minimalistic smart array (container) class template

    - by legends2k
    I've written a (array) container class template (lets call it smart array) for using it in the BREW platform (which doesn't allow many C++ constructs like STD library, exceptions, etc. It has a very minimal C++ runtime support); while writing this my friend said that something like this already exists in Boost called MultiArray, I tried it but the ARM compiler (RVCT) cries with 100s of errors. I've not seen Boost.MultiArray's source, I've started learning templates only lately; template meta programming interests me a lot, although am not sure if this is strictly one that can be categorized thus. So I want all my fellow C++ aficionados to review it ~ point out flaws, potential bugs, suggestions, optimizations, etc.; something like "you've not written your own Big Three which might lead to...". Possibly any criticism that will help me improve this class and thereby my C++ skills. Edit: I've used std::vector since it's easily understood, later it will be replaced by a custom written vector class template made to work in the BREW platform. Also C++0x related syntax like static_assert will also be removed in the final code. smart_array.h #include <vector> #include <cassert> #include <cstdarg> using std::vector; template <typename T, size_t N> class smart_array { vector < smart_array<T, N - 1> > vec; public: explicit smart_array(vector <size_t> &dimensions) { assert(N == dimensions.size()); vector <size_t>::iterator it = ++dimensions.begin(); vector <size_t> dimensions_remaining(it, dimensions.end()); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimensions[0], temp_smart_array); } explicit smart_array(size_t dimension_1 = 1, ...) { static_assert(N > 0, "Error: smart_array expects 1 or more dimension(s)"); assert(dimension_1 > 1); va_list dim_list; vector <size_t> dimensions_remaining(N - 1); va_start(dim_list, dimension_1); for(size_t i = 0; i < N - 1; ++i) { size_t dimension_n = va_arg(dim_list, size_t); assert(dimension_n > 0); dimensions_remaining[i] = dimension_n; } va_end(dim_list); smart_array <T, N - 1> temp_smart_array(dimensions_remaining); vec.assign(dimension_1, temp_smart_array); } smart_array<T, N - 1>& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() const { return vec.size(); } }; template<typename T> class smart_array<T, 1> { vector <T> vec; public: explicit smart_array(vector <size_t> &dimension) : vec(dimension[0]) { assert(dimension[0] > 0); } explicit smart_array(size_t dimension_1 = 1) : vec(dimension_1) { assert(dimension_1 > 0); } T& operator[](size_t index) { assert(index < vec.size() && index >= 0); return vec[index]; } size_t length() { return vec.size(); } }; Sample Usage: #include "smart_array.h" #include <iostream> using std::cout; using std::endl; int main() { // testing 1 dimension smart_array <int, 1> x(3); x[0] = 0, x[1] = 1, x[2] = 2; cout << "x.length(): " << x.length() << endl; // testing 2 dimensions smart_array <float, 2> y(2, 3); y[0][0] = y[0][1] = y[0][2] = 0; y[1][0] = y[1][1] = y[1][2] = 1; cout << "y.length(): " << y.length() << endl; cout << "y[0].length(): " << y[0].length() << endl; // testing 3 dimensions smart_array <char, 3> z(2, 4, 5); cout << "z.length(): " << z.length() << endl; cout << "z[0].length(): " << z[0].length() << endl; cout << "z[0][0].length(): " << z[0][0].length() << endl; z[0][0][4] = 'c'; cout << z[0][0][4] << endl; // testing 4 dimensions smart_array <bool, 4> r(2, 3, 4, 5); cout << "z.length(): " << r.length() << endl; cout << "z[0].length(): " << r[0].length() << endl; cout << "z[0][0].length(): " << r[0][0].length() << endl; cout << "z[0][0][0].length(): " << r[0][0][0].length() << endl; // testing copy constructor smart_array <float, 2> copy_y(y); cout << "copy_y.length(): " << copy_y.length() << endl; cout << "copy_x[0].length(): " << copy_y[0].length() << endl; cout << copy_y[0][0] << "\t" << copy_y[1][0] << "\t" << copy_y[0][1] << "\t" << copy_y[1][1] << "\t" << copy_y[0][2] << "\t" << copy_y[1][2] << endl; return 0; }

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  • why i add more insignificant code but cost less time

    - by user3714382
    i write a method and when i add some insignificant code it works faster, like these : array[1]=array[1]; array[0]=array[0]; array[3]=array[3]; array[2]=array[2]; i use double t=System.currentTimeMillis(); at first to record the time. then call the method and use System.out.println(System.currentTimeMillis()-t); in the end. when i delete the code (array[1]=array[1];...) the cost time is 1035.0 ms,but if i add these code, the cost time become 898.0ms. here is my method and my code. PS:this method is use for the game 2048, exp: {2,2,2,2} trans to {0,0,4,4} static void toRight2(int[] array){ if (array[2]==array[3] ) { array[3]=array[2]*2; if (array[0]==array[1]) { array[2]=array[1]*2; array[0]=0; array[1]=0; }else { array[2]=array[1]; array[1]=array[0]; array[0]=0; } } else{ if (array[0]==array[1]) { array[1]=array[1]*2; array[0]=0; array[3]=array[3]; array[2]=array[2]; }else { array[1]=array[1];//delete this cost more time array[0]=array[0];//delete this cost more time array[3]=array[3];//delete this cost more time array[2]=array[2];//delete this cost more time } } } public static void main(String[] args) { double t=System.currentTimeMillis(); int[] array={1,2,3,3}; for (int j = 2; j <400*1000000; j++) { toRight2(array); } System.out.println(System.currentTimeMillis()-t); }

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  • Large sparse (stiff) ODE system needed for testing

    - by macydanim
    I hope this is the right place for this question. I have been working on a sparse stiff implicit ODE solver and have finished the code so far. I now tested the solver with the Van der Pol equation, and another stiff problem, which is of dimension 4. But to perform better tests I am searching for a bigger system. I'm thinking of the order N = 100...1000, if possible stiff and sparse. Does anybody have an example I could use? I really don't know where to search.

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  • PL/SQL bulk collect into associative array with sparse key

    - by Dan
    I want to execute a SQL query inside PL/SQL and populate the results into an associative array, where one of the columns in the SQL becomes the key in the associative array. For example, say I have a table Person with columns PERSON_ID INTEGER PRIMARY KEY PERSON_NAME VARCHAR2(50) ...and values like: PERSON_ID | PERSON_NAME ------------------------ 6 | Alice 15 | Bob 1234 | Carol I want to bulk collect this table into a TABLE OF VARCHAR2(50) INDEX BY INTEGER such that the key 6 in this associative array has the value Alice and so on. Can this be done in PL/SQL? If so, how?

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  • passing an array structure as an array

    - by Matias
    I'm having trouble passing a structure array as a parameter of a function struct Estructure{ int a; int b; }; and a funtion Begining(Estructure &s1[]) { //modifi the estructure s1 }; and the main would be something like this int main() { Estructure m[200]; Begining(m); }; is this valid?

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  • Reset array keys in multidimensional array

    - by nbaumann
    I've been looking around for a solution to this with no real success. I have a multidimensional array of parents and children with no limits on depth. This is generated from a database but the issue is that the item ID becomes the key using my way of arranging a flat array into a multidimensional array like so: Array( [28] => Array ( [id] => 28 [color] => #ff24e5 [name] => Personal [parent_id] => [children] => Array ( [23] => Array ( [id] => 23 [color] => #41c3a3 [name] => Shopping [parent_id] => 28 [children] => Array ( [22] => Array ( [id] => 22 [color] => #8be32b [name] => Deals [parent_id] => 23 [children] => Array ( ) ) ) ) [150] => Array ( [id] => 150 [color] => #e9a3f0 [name] => Orders [parent_id] => 28 [children] => Array ( ) ) ) ) ) What I would like, is a function that does the following: Array ( [0] => Array ( [id] => 28 [color] => #ff24e5 [name] => Personal [parent_id] => [children] => Array ( [0] => Array ( [id] => 23 [color] => #41c3a3 [name] => Shopping [parent_id] => 28 [children] => Array ( [0] => Array ( [id] => 22 [color] => #8be32b [name] => Deals [user_id] => 1 [selected] => 0 [parent_id] => 23 [children] => Array ( ) ) ) ) [1] => Array ( [id] => 150 [color] => #e9a3f0 [name] => Orders [parent_id] => 28 [children] => Array ( ) ) ) ) ) Essentially reassign keys starting from 0. I've tried numerous methods, but I'm assuming that I need to find a recursive solution and when I tried that, it destroyed my array. I was reading up on the array_walk_recursive() function, but I don't quite know what to do beyond that. Essentially, is there a way to reset numeric keys in a multidimensional array? Thanks for the help!

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