#include<stdio.h>
#include<string.h>
int main(void){

    char A[10000+1];
    int sum=0,i=0;
    scanf("%s",A);
    while(1)
        if(A[i]!=EOF){
            if('0'<A[i]&&A[i]<='9'){
                sum+=A[i]-'0';
            }
            i++;
        if(A[i]==EOF){
            break;
        }
        }
        
    printf("%d\n",sum);
    return 0;

}