#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>

using namespace std;

int main()
{
    char str[10000];
    scanf("%s", str);
    
    int answer = 0;

    for (int i = 0; i < 10000; i++ ){
        char c = str[i];

        if (c == '\0') {
            break;
        }

        if(isdigit(c)) {
            answer += atoi(&c);
        }
    }

    printf("%d\n", answer);
}