Write a c program to find out the sum of series 1 + 2 + …. + n

Mathematical Formula:

Sum of the series 1 + 2 + 3 + … + n = n (n+1)/2

C Program

#include<stdio.h>
int main() {
	int n,i;
	int sum=0;
	printf("Enter the n i.e. max values of series: ");
	scanf("%d",&n);
	sum = (n * (n + 1)) / 2;
	printf("Sum of the series: ");
	for (i =1;i <= n;i++) {
		if (i!=n)
		             printf("%d + ",i); else
		             printf("%d = %d ",i,sum);
	}
	return 0;
}

Output:

Enter the n i.e. max values of series: 5
Sum of the series: 1 + 2 + 3 + 4 + 5 = 15