### Determine the sum of the even numbers between 1 and n

Determine the sum of the even numbers between 1 and n. n is specified by the user. Allow the user to repeat the process terminate if the user enters zero (0)
Example:
If the user enters 16, compute the sum of 2 + 4 + 6 + …16
If the user enters 21, compute the sum of 2 + 4 + 6 + …18 + 20
if the user enters 0 stop

Here is my code

 ``1234567891011121314151617181920212223242526272829303132333435`` ``````#include using namespace std; int main() { int n = 0; int j = 0; int sum = 0; char again = ' '; sum = 0; j = 2; cout << "Enter a number: " ; cin >> n; while (j <= n) { if (j%2==0) { sum = sum + j; j = j+2; } } cout << "the sum of even numbers from 1 to " << n << " is " << sum << endl; cout << "Do you want to do this again (Y/N)?"; cin >> again; again = toupper(again); while (toupper(again) == 'Y') { ; } system("pause"); return 0; }``````

This is as far as I have gotten. I have tried several things to make it work and can't seem to get it figured out.
you need a nested loop. Here is the psuedo code to get you going:

 ``12345678910111213141516171819202122232425262728293031`` ``````#include #include using namespace std; int main() { int n = 0; int j = 0; int sum = 0; char again = 'Y'; sum = 0; j = 2; // Loop 1: if again is y or Y then you want you go through this loop (remember or is designated ||) { // opening bracket of first loop cout << "Enter a number: " ; cin >> n; sum=0; //Loop 2: Calculate sum of the even's. Start with j at 2 and increment it by 2 until it equals or is less than the number chosen by the user cout << "the sum of even numbers from 1 to " << n << " is " << sum << endl; cout << "Do you want to do this again (Y/N)?"; cin >> again; //if they put in y or Y for this statement then the original loop will repeat }//closing bracket of first loop return 0; } ``````
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I used what you said, and it didn't run the way it is supposed to.
This should do the trick

 ``12345678910111213141516171819202122232425262728293031323334`` ``````#include #include using namespace std; int main() { int n = 0; int j = 0; int sum = 0; char again = 'Y'; sum = 0; j = 2; while (again=='y' || again=='Y') { cout << "Enter a number: " ; cin >> n; sum=0; for(j=2;j<=n; j+=2) { sum += j; } cout << "the sum of even numbers from 1 to " << n << " is " << sum << endl; cout << "Do you want to do this again (Y/N)?"; cin >> again; } return 0; } ``````
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