题解 | #The Biggest
The Biggest Water Problem
https://www.nowcoder.com/practice/435aa556e093463891f6da7d322140a4
#include <stdio.h> int main() { int n=0; scanf("%d",&n); while(n>=10) { int sum=0; while(n) { sum=sum+n%10; n/=10; } n=sum; } printf("%d",n); return 0; }