Find the sum of all natural numbers between 1 to n with C.

#include <stdio.h>

int main()
{
    int i, N, sum = 0;

    printf("Enter Last Number N : ");
    scanf("%d", &N);

    for (i = 1; i <= N; i++)
    {
        sum += i;
    }

    printf("Sum  %d natural numbers = %d", N, sum);

    return 0;
}

Output:-


Enter Last Number N : 10
Sum 10 natural numbers = 55