Thread: Sum of numbers

The purpose of this program is to display the sums of all of the numbers from one to the input number. Example if i enter 5 i want it to add the numbers 1+2+3+4+5 = 15 or if i enter 225 it will add 1+2+.....225

Here is what i am working with

insert

Code:

#include <iostream.h>

void main()
{
int Number, Sum;
Sum = 0;
cout << "Enter a number: " << endl;
cin >> Number;

while (Number >= 0)
{
Sum = Sum + Number;
cout << "Current Total " << Sum << endl;
cout << "Enter a number: " << endl;
cin >> Number;

} 

cout << "The total is " << Sum << endl;

}

It works fine when i go in order 1+2+3+.....10 but it does not add all i need.

Any hints will help thanks in advance.

Code:

std::cout << (Number*(Number+1)/2) << std::endl;

or, if you want to learn programming, consider two loops. I am going to write the outer loop for you, because this is a good habit to get into early while you are learning

Code:

while(std::cin >> Number && Number > 0) {
    int Sum = 0;
    for(....)
    std::cout << Sum;
}

This solves a lot of common bugs, first off realize that && is left to right, so the left hand side gets evaluated first, the right hand side is evaluated only when the left is true. The result of a stream input operation, is a stream. This is what lets you do cin >> a >> b; If you evaluate a stream in a boolian context it is true only if all the operations prior to this have been successful. If someone inputs 15, and then a letter your program loops forever, when done this way it exits.