View Code of Problem 30

#include<stdio.h> 
#include<string.h>
#include<math.h>
int main(){ 
    int n,i,sum;
    while(scanf("%d",&n)!=EOF){
    	sum=0;
    	for(i=1;i<=n;i++)
      sum+=i;
    printf("%d\n",sum);
	}
    
	return 0;
}