I'm writing a program to ask the user to enter a value between 5 and 21 (inclusive). If the number entered is not in this range, it prints, "Please try again". If the number is within the range, I need to take that number, and print the sum of all the numbers from 1 to the value entered. So if the user entered "7", the sum would be "28". I successfully wrote the first loop, in the case of the number not being within the range, but cannot figure out how to run the second loop- whether to use a while, do-while, or for loop. Please advise.

#include <iostream> 

int main () { 
    int uservalue; 
    int count; 
    int sum; 

    //Prompt user for input 
    do {
        cout << "Enter a value from 5 to 21: "; 
        cin >> uservalue; 

        if (uservalue < 5 || uservalue > 21)
            cout << "Value out of range. Try again..." << endl; 

     } while (uservalue < 5 || uservalue > 21); 

    cout << endl; 

    //Loop to accumulate sum
    for (count = 1, count < uservalue, count++;) {
        sum = uservalue + count; 
        if (uservalue <= 5 || uservalue <= 21)
            cout << the sum is " << sum << endl; 
    } 

    return 0; 
}