#include<iostream> //输入函数库 #include<iomanip> #include<cmath> //数学函数库 #include<cstdio> #include<ctime> #include<cstring> #include<cstdlib> #include<string> #include<stdlib.h> #include<sys/time.h> using namespace std; int main(){ int a,b,c,d; cin>>a; b=a%10; c=a/10%10; d=a/100%10; cout<<b+c+d; return 0; }