// sum upto given number
#include <stdio.h>

int main() {
    int sum=0,n;
    printf("Enter number upto which you need the sum : ");
    scanf("%d",&n);
    printf("\n");
    for(int i=1,j=n;i<=n && j>=1;i++,j--){
        sum = sum + i; //sum+=i
        printf("%d\n",j);
    }
    printf("sum is %d\n",sum);
    return 0;
}