#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf()) #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int x,a,b,c; cin>>x; a=x%10; b=x%100/10; c=x/100; cout<<a+b+c; return 0; }