# C program to find sum of all numbers from 0 to N without using loop

Here, we are implementing a C program that will be used to find the sum of all numbers from 0 to N without using loop.
Submitted by IncludeHelp, on September 04, 2018

Given the value of N and we have to find sum of all numbers from 0 to N in C language.

To find the sum of numbers from 0 to N, we use a mathematical formula: N(N+1)/2

Example:

```    Input:
Enter value of N: 5
Logic/formula:
sum = N*(N+1)/2 = 5*(5+1)/2 =5*6/2 = 15
Output:
sum = 15

Input:
Enter value of N: 10
Logic/formula:
sum = N*(N+1)/2 = 10*(10+1)/2 =10*11/2 = 110/2 = 55
Output:
sum = 55
```

Program:

```#include <stdio.h>

int main(void) {

int n, sum;

//input value of n
printf("Enter the value of n: ");
scanf("%d", &n);

//initialize sum with 0
sum =0;

//use formula to get the sum from 0 to n
sum = n*(n+1)/2;

//print sum
printf("sum = %d\n", sum);

return 0;
}
```

Output

```    Run1:
Enter the value of n: 5
sum = 15

Run2:
Enter the value of n: 10
sum = 55
```