#include <stdio.h>
int main(void){
    int ans = 0;
    int i = 0;
    char c;
    while( i++ < 10000 ){
        c = getchar();
        if( c == EOF ){
           break; 
        }
        if( c >= 49 && c <= 57 ){
            ans += c - 48;
        }
    }
    printf( "%d\n", ans );
}