Suppose I have a column with words:
orange
grape
orange
orange
apple
orange
grape
banana
How do I execute a query to get the top 10 words, as well as their count?
hello i am a student and i am doing my senior project it is about developing an application in j2me for scanning a barcode and extract the number of the barcode in a message to be send.
please i search the net but i cant found something usefull i am new at j2me if someone could help me with sourch code and how to create it i will be very thankfull my email is [email protected]
thanks in advanced
This an extract from an c program that should demonstrate a bufferoverflow.
void foo()
{
char arr[8];
printf(" enter bla bla bla");
gets(arr);
printf(" you entered %s\n", arr);
}
The question was "How many input chars can a user maximal enter without a creating a buffer overflow"
My initial answer was 8, because the char-array is 8 bytes long.
Although I was pretty certain my answer was correct, I tried a higher amount of chars, and found that the limit of chars that I can enter, before I get a segmentation fault is 11. (Im running this on A VirtualBox Ubuntu)
So my question is: Why is it possible to enter 11 chars into that 8 byte array?
Hi,
For some reason, I can't get this program to work. I've had other CS majors look at it and they can't figure it out either.
This program performs the Jacobi algorithm (you can see step-by-step instructions and a MATLAB implementation here). BTW, it's different from the Wikipedia article of the same name.
Since NSArray is one-dimensional, I added a method that makes it act like a two-dimensional C array. After running the Jacobi algorithm many times, the diagonal entries in the NSArray (i[0][0], i[1][1], etc.) are supposed to get bigger and the others approach 0. For some reason though, they all increase exponentially. For instance, i[2][4] should equal 0.0000009, not 9999999, while i[2][2] should be big.
Thanks in advance,
Chris
NSArray+Matrix.m
@implementation NSArray (Matrix)
@dynamic offValue, transposed;
- (double)offValue {
double sum = 0.0;
for ( MatrixItem *item in self )
if ( item.nonDiagonal )
sum += pow( item.value, 2.0 );
return sum;
}
- (NSMutableArray *)transposed {
NSMutableArray *transpose = [[[NSMutableArray alloc] init] autorelease];
int i, j;
for ( i = 0; i < 5; i++ ) {
for ( j = 0; j < 5; j++ ) {
[transpose addObject:[self objectAtRow:j andColumn:i]];
}
}
return transpose;
}
- (id)objectAtRow:(NSUInteger)row andColumn:(NSUInteger)column {
NSUInteger index = 5 * row + column;
return [self objectAtIndex:index];
}
- (NSMutableArray *)multiplyWithMatrix:(NSArray *)array {
NSMutableArray *result = [[NSMutableArray alloc] init];
int i = 0, j = 0, k = 0;
double value;
for ( i = 0; i < 5; i++ ) {
value = 0.0;
for ( j = 0; j < 5; j++ ) {
for ( k = 0; k < 5; k++ ) {
MatrixItem *firstItem = [self objectAtRow:i andColumn:k];
MatrixItem *secondItem = [array objectAtRow:k andColumn:j];
value += firstItem.value * secondItem.value;
}
MatrixItem *item = [[MatrixItem alloc] initWithValue:value];
item.row = i;
item.column = j;
[result addObject:item];
}
}
return result;
}
@end
Jacobi_AlgorithmAppDelegate.m
// ...
- (void)jacobiAlgorithmWithEntry:(MatrixItem *)entry {
MatrixItem *b11 = [matrix objectAtRow:entry.row andColumn:entry.row];
MatrixItem *b22 = [matrix objectAtRow:entry.column andColumn:entry.column];
double muPlus = ( b22.value + b11.value ) / 2.0;
muPlus += sqrt( pow((b22.value - b11.value), 2.0) + 4.0 * pow(entry.value, 2.0) );
Vector *u1 = [[[Vector alloc] initWithX:(-1.0 * entry.value) andY:(b11.value - muPlus)] autorelease];
[u1 normalize];
Vector *u2 = [[[Vector alloc] initWithX:-u1.y andY:u1.x] autorelease];
NSMutableArray *g = [[[NSMutableArray alloc] init] autorelease];
for ( int i = 0; i <= 24; i++ ) {
MatrixItem *item = [[[MatrixItem alloc] init] autorelease];
if ( i == 6*entry.row )
item.value = u1.x;
else if ( i == 6*entry.column )
item.value = u2.y;
else if ( i == ( 5*entry.row + entry.column ) || i == ( 5*entry.column + entry.row ) )
item.value = u1.y;
else if ( i % 6 == 0 )
item.value = 1.0;
else
item.value = 0.0;
[g addObject:item];
}
NSMutableArray *firstResult = [[g.transposed multiplyWithMatrix:matrix] autorelease];
matrix = [firstResult multiplyWithMatrix:g];
}
// ...
write a script that takes two optional boolean arguments,"--verbose‚" and ‚"--live", and two required string arguments, "base"and "pattern". Please set up the command line processing using argparse.
This is the code I have so far for the question, I know I am getting close but something is not quite right. Any help is much appreciated.Thanks for all the quick useful feedback.
def main():
import argparse
parser = argparse.ArgumentParser(description='')
parser.add_argument('base', type=str)
parser.add_arguemnt('--verbose', action='store_true')
parser.add_argument('pattern', type=str)
parser.add_arguemnt('--live', action='store_true')
args = parser.parse_args()
print(args.base(args.pattern))
Question 2. USE THE FOR LOOP.
Design and write an algorithm that will read a single positive number from the keyboard and will then print a pyramid out on the screen. The pyramid will need to be of a height equal in lines to the number inputted by the operator. Your program is not to test for negative numbers, nor is it to cater for them. For your test, use the number 7. If you would like to take the problem further, try 18 and watch what happens.
Example input:
4
Example output:
1
121
12321
1234321
I have a datetime.date variable in python.I need to pass it to a function do operations according to the date given and then increment the date for the next set of operations.The problem is I have to do the operations in diff pages and hence I need the date as a variable which can go from page to page. Can we do this in python.......
Hello everyone.
I still have a question about Enumerations. Here's a quick sketch of the situation.
I have a class Backpack that has a Hashmap content with as keys a variable of type long, and as value an ArrayList with Items.
I have to write an Enumeration that iterates over the content of a Backpack. But here's the catch: in a Backpack, there can also be another Backpack. And the Enumeration should also be able to iterate over the content of a backpack that is in the backpack. (I hope you can follow, I'm not really good at explaining..)
Here is the code I have:
public Enumeration<Object> getEnumeration() {
return new Enumeration<Object>() {
private int itemsDone = 0;
//I make a new array with all the values of the HashMap, so I can use
//them in nextElement()
Collection<Long> keysCollection = getContent().keySet();
Long [] keys = keysCollection.toArray(new Long[keysCollection.size()]);
public boolean hasMoreElements() {
if(itemsDone < getContent().size()) {
return true;
}else {
return false;
}
}
public Object nextElement() {
ArrayList<Item> temporaryList= getContent().get(keys[itemsDone]);
for(int i = 0; i < temporaryList.size(); i++) {
if(temporaryList.get(i) instanceof Backpack) {
return temporaryList.get(i).getEnumeration();
}else {
return getContent().get(keys[itemsDone++]);
}
}
}
};
Will this code work decently? It's just the "return temporaryList.get(i).getEnumeration();" I'm worried about. Will the users still be able to use just the hasMoreElemens() and nextElement() like he would normally do?
Any help is appreciated,
Harm De Weirdt
Am I wondering if the follow are true.
If f(n) is O(g(n)) and f(n) is also O(g(n)) that means
f(n) is also big T(g(n)) right? Also if either of the 2 above are false, then f(n) is not big T(g(n))?
These questions are a kind of game, and I did not find the solution for them.
It is possible to write ::: in C++ without using quotes or anything like this and the compiler will accept it (macros are prohibited too).
And the same is true for C# too, but in C#, you have to write ???.
I think C++ will use the :: scope operator and C# will use ? : , but I do not know the answers to them.
Any idea?
I have some big numbers (again) and i need to find if the sum of the digits is an even number.
I tried this: finding the sum of the digits with a while loop and then checking if that sum % 2 equals 0 and it's working but it's too slow for big numbers, because i am given intervals of numbers and if the input is 1999999 19999999999 then my program fails, i cannot complete within the time limit which is 0,1 sec.
What to do ? Is there any other faster way to do this ?
EDIT: The input 1999999 19999999999 means it will start with 1999999 and check all the numbers like i wrote above until 19999999999, and because we are talking about big numbers (< 2^30) my program is not worthy.
I like to read alot of IT books e.g programming / functional. But the problem is that after reading I cannot find reasons to put it into practise and I soon forget what I read.
Any advise?
I'm working on a Serpinski triangle program that asks the user for the levels of triangles to draw. In the interests of idiot-proofing my program, I put this in:
Scanner input= new Scanner(System.in);
System.out.println(msg);
try {
level= input.nextInt();
} catch (Exception e) {
System.out.print(warning);
//restart main method
}
Is it possible, if the user punches in a letter or symbol, to restart the main method after the exception has been caught?
I have tried to this query: What are the doctors that work on less than 2 Hospitals.
I have these tables:
CREATE TABLE Hospital (
hid INT PRIMARY KEY,
name VARCHAR(127) UNIQUE,
country VARCHAR(127),
area INT
);
CREATE TABLE Doctor (
ic INT PRIMARY KEY,
name VARCHAR(127),
date_of_birth INT,
);
CREATE TABLE Work (
hid INT,
ic INT,
since INT,
FOREIGN KEY (hid) REFERENCES Hospital (hid),
FOREIGN KEY (ic) REFERENCES Doctor (ic),
PRIMARY KEY (hid,ic)
);
I tried with this:
SELECT DISTINCT D.ic
FROM Doctor D, Work W
JOIN Hospital H ON (H.hid = W.hid)
WHERE D.bi = W.bi
GROUP BY (D.ic)
HAVING COUNT(H.hid) < 2
;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JApplet;
import javax.swing.Timer;
public class CountingSheep extends JApplet
{
private Image sheepImage;
private Image backgroundImage;
private GameBoard gameBoard;
private scoreBoard scoreBoard;
public void init()
{
loadImages();
gameBoard = new GameBoard(sheepImage, backgroundImage);
scoreBoard = new scoreBoard();
getContentPane().add(gameBoard);
getContentPane().add(scoreBoard);
}
public void loadImages()
{
sheepImage = getImage(getDocumentBase(), "sheep.png");
backgroundImage = getImage(getDocumentBase(), "bg.jpg");
}
}
Update guys:
Alright, first of all, thank you very much for all the help you've given so far (specifically creemam and Hovercraft Full of Eels), and your persistence. You've helped me out a lot as this is incredibly important (i.e. me passing my degree). The problem now is:
The program works correctly when nothing but the GameBoard class is added to the JApplet, however, when I try to add the ScoreBoard class, both Panel classes do not show on the Applet. I'm guessing this is now down to positioning? Any ideas?
EDIT: Gone back to the previously asked question Hovercraft, and found it was due to the layout of the contentPane and the order at with the components were added. Thanks to all of you so much. People like you make the development community a bit of alright.
#include<iostream.h>
void main()
{
cout<<"Love";
}
The question is how can we change the output of this program into
"I Love You" by without making any change in main().
void display_totals();
int exam1[100][3];// array that can hold 100 numbers for 1st column
int exam2[100][3];// array that can hold 100 numbers for 2nd column
int exam3[100][3];// array that can hold 100 numbers for 3rd column
int main()
{
int go,go2,go3;
go=read_file_in_array;
go2= calculate_total(exam1[],exam2[],exam3[]);
go3=display_totals;
cout << go,go2,go3;
return 0;
}
void display_totals()
{
int grade_total;
grade_total=calculate_total(exam1[],exam2[],exam3[]);
}
int calculate_total(int exam1[],int exam2[],int exam3[])
{
int calc_tot,above90=0, above80=0, above70=0, above60=0,i,j;
calc_tot=read_file_in_array(exam[100][3]);
exam1[][]=exam[100][3];
exam2[][]=exam[100][3];
exam3[][]=exam[100][3];
for(i=0;i<100;i++);
{
if(exam1[i] <=90 && exam1[i] >=100)
{
above90++;
cout << above90;
}
}
return exam1[i],exam2[i],exam3[i];
}
int read_file_in_array(int exam[100][3])
{
ifstream infile;
int num, i=0,j=0;
infile.open("grades.txt");// file containing numbers in 3 columns
if(infile.fail()) // checks to see if file opended
{
cout << "error" << endl;
}
while(!infile.eof()) // reads file to end of line
{
for(i=0;i<100;i++); // array numbers less than 100
{
for(j=0;j<3;j++); // while reading get 1st array or element
infile >> exam[i][j];
cout << exam[i][j] << endl;
}
}
infile.close();
return exam[i][j];
}
I've made a simple Javascript code for a shopping basket but now I have realised that I have made a error with making it and don't know how to fix it. What I have is Javascript file but I have also included the images source and the addtocart button as well, but What I am trying to do now is make 2 files one a .HTML file and another .JS file, but I can't get it to because when I make a button in the HTML file to call the function from the .JS file it won't work at all.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<HTML>
<HEAD><TITLE>shopping</TITLE>
<META http-equiv=Content-Type content="text/html; charset=UTF-8">
<STYLE type=text/CSS>
fieldset{width:300px}
legend{font-size:24px;font-family:comic sans ms;color:#004455}
</STYLE>
<META content="MSHTML 6.00.2900.2963" name=GENERATOR></HEAD>
<BODY scroll="auto">
<div id="products"></div><hr>
<div id="inCart"></div>
<SCRIPT type="text/javascript">
var items=['Xbox~149.99','StuffedGizmo~19.98','GadgetyGoop~9.97'];
var M='?'; var product=[]; var price=[]; var stuff='';
function wpf(product,price){var pf='<form><FIELDSET><LEGEND>'+product+'</LEGEND>';
pf+='<img src="../images/'+product+'.jpg" alt="'+product+'" ><p>price '+M+''+price+'</p> <b>Qty</b><SELECT>';
for(i=0;i<6;i++){pf+='<option value="'+i+'">'+i+'</option>'} pf+='</SELECT>';
pf+='<input type="button" value="Add to cart" onclick="cart()" /></FIELDSET></form>';
return pf
}
for(j=0;j<items.length;j++){
product[j]=items[j].substring(0,items[j].indexOf('~'));
price[j]=items[j].substring(items[j].indexOf('~')+1,items[j].length);
stuff+=''+wpf(product[j],price[j])+'';
}
document.getElementById('products').innerHTML=stuff;
function cart(){ var order=[]; var tot=0
for(o=0,k=0;o<document.forms.length;o++){
if(document.forms[o].elements[1].value!=0){
qnty=document.forms[o].elements[1].value;
order[k]=''+product[o]+'_'+qnty+'*'+price[o]+'';
tot+=qnty*price[o];k++
}
}
document.getElementById('inCart').innerHTML=order.join('<br>')+'<h3>Total '+tot+'</h3>';
}
</SCRIPT>
<input type="button" value="Add to cart" onclick="cart()" /></FIELDSET></form>
</BODY></HTML>
Hello,
I need help dealing with an array in my java program. in my first class, "test", I set 4 variables and then send them to my other class (test2).
arr[i] = new test2(id, fname, lname, case);
at that point, variables are set and then I want to return those variables. So in the test2 class, I have a method that strictly returns one of those variables
public int getId(){
return id;
}
I understand this is a little stupid, but professor gets what professor wants I guess. What I want to do now is in my main method in "test" I want to retrieve that variable and sort the array based on that int. Unfortunately, I have to create my own sort function, but I think this would work for what I want to do.
for(j = 0; j < arr.length; j++){
int indexMin =j;
for(i = j; i < arr.length;i++){
if(arr[i] < arr[indexMin]){
indexMin = i;
}
}
int tmp = arr[j];
arr[j] = arr[indexMin];
arr[indexMin] = tmp;
}
I appreciate any help anyone could provide.
Thank you
Hello,
I hear 3 years ago problem and apparently have infinity solutions.
I want to find one of this infinity set.
Problem: Write program (have only one file example "selfsource.c") who printing on stdout self source code and exits.
All techniques all alowed. Anyone can help me?
I created a class "Entry" to handle Dictionary entries, but in my main(), I create the Entry() and try to cout the char typed public members, but I get garbage. When I look at the Watch list in debugger, I see the values being set, but as soon as I access the values, there is garbage. Can anyone elaborate on what I might be missing?
#include <iostream>
using namespace std;
class Entry
{
public:
Entry(const char *line);
char *Word;
char *Definition;
};
Entry::Entry(const char *line)
{
char tmp[100];
strcpy(tmp, line);
Word = strtok(tmp, ",") + '\0';
Definition = strtok(0,",") + '\0';
}
int main()
{
Entry *e = new Entry("drink,What you need after a long day's work");
cout << "Word: " << e->Word << endl;
cout << "Def: " << e->Definition << endl;
cout << endl;
delete e;
e = 0;
return 0;
}
I have 3 tables -
Items,
Props,
Items_To_Props
i need to return all items that match all properties that i send
example
items
1
2
3
4
props
T1
T2
T3
items_to_props
1 T1
1 T2
1 T3
2 T1
3 T1
when i send T1,T2 i need to get only item 1
I want Java code that can compare in this way (for example):
<1 2 3 4> = <3 1 2 4>
<1 2 3 4> != <3 4 1 1>
I can't use hashmap table or anything; just pure code without library.
I know there are two ways.
sort them and compare the array index by index
use two for loops and compare the outer index with the inner index. I have been trying with this but still not working:
for(int i = 0; i < n; i++)
{
for(int j = 0; j < n; j++)
{
if(a[i] != a[j] && j == n)
return false;
}
}
return true;
anything wrong with the code ? thanks
In the university we were given the following code sample and we were being told, that there is a memory leak when running this code. The sample should demonstrate that this is a situation where the garbage collector can't work.
As far as my object oriented programming goes, the only codeline able to create a memory leak would be
items=Arrays.copyOf(items,2 * size+1);
The documentation says, that the elements are copied. Does that mean the reference is copied (and therefore another entry on the heap is created) or the object itself is being copied? As far as I know, Object and therefore Object[] are implemented as a reference type. So assigning a new value to 'items' would allow the garbage collector to find that the old 'item' is no longer referenced and can therefore be collected.
In my eyes, this the codesample does not produce a memory leak. Could somebody prove me wrong? =)
import java.util.Arrays;
public class Foo
{
private Object[] items;
private int size=0;
private static final int ISIZE=10;
public Foo()
{
items= new Object[ISIZE];
}
public void push(final Object o){
checkSize();
items[size++]=o;
}
public Object pop(){
if (size==0)
throw new ///...
return items[--size];
}
private void checkSize(){
if (items.length==size){
items=Arrays.copyOf(items,2 * size+1);
}
}
}