#include<bits/stdc++.h> using namespace std; int main(){ int a,g,s,b; cin>>a; g=a%10; s=a/10%10; b=a/100; cout<<g+s+b; return 0; }

#include<bits/stdc++.h> using namespace std; int main() { int x,s; cin>>x; if(x>=100&&x<=999) { s=x/100+x%100/10+x%100%10; cout<<s; } return 0; }

#include<bits/stdc++.h>

using namespace std;

int main()

{

int x,s;

cin>>x;

if(x>=100&&x<=999)
{

s=x/100+x%100/10+x%100%10;

cout<<s;

}

}