求解答，上周刚刚学完while语句和for循环，遇到了问题

Question

请问，我这道是哪里出现了问题，我该如何求解？只让用while语句

Answer 1

 
#include <stdio.h>
int main()
{
    int i = 1,n;
    double s = 0;
    scanf("%d",&n);
    while(i <= n){
        s += (1.0) / (i * (i + 1));
        i++;
    }
    printf("%lf",s);
    return 0;
}