数根

#include <iostream>using namespace std;int fun(int t){int k=0;while (t!=0){k+=t%10;t=t/10;}return k;}int main(){int n,i,sum=0;char a[1010];cin >> n;while (n--){sum=0;cin >> a;for (i=0;a[i]!='\0';i++){sum+=a[i]-'0';}while(sum>=10){sum=fun(sum);}cout << sum << endl;}return 0;}