#include <stdio.h>
#include <string.h>
char num[1000001];
int total[1000000]={0};
int main() {

    int cnt=0;
    scanf("%s",num);
    int len=strlen(num);
    int two=0;
    int n=0;
    for(int i=len-1; i>=0; i--) {
        int x=num[i]-'0';
        if(two==0) {
            total[cnt]+=x;
            two++;
        } else if(two==1) {
            total[cnt]+=2*x;
            two++;
        } else if (two==2){
            total[cnt]+=4*x;
            if(i>0) {
                two=0;
                cnt++;
            }
        }
    }
    for(int i=cnt;i>=0; i--) {
        printf("%d",total[i]);
    }
    return 0;
}

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