#include <bits/stdc++.h>

using ll = long long;

using namespace std;

int main()
{
    char s[10001]={};
    char* p=&s[0];
    
    scanf("%s",&s[0]);
    ll sum{0};
    
    while (*p)
    {
        if ((*p>='0') && (*p<='9'))
        {
            sum+=*p-'0';
        }
        ++p;
    }
    
    printf("%lld\n",sum);

    return 0;
}