017

017

#include <iostream>  
#include <cstdio>  
using namespace std;  
int main() {  
    string s;  
    cin >> s;  
    int flag = (s[0] == '-' ? 1 : 0);  
    int len = s.length();  
    int bit = len - flag;  
    int cnt = 0;  
    for(int i = 0; i < len; i++) {  
        if(s[i] == '2')  
            cnt++;  
    }  
    double ans = (double)cnt / bit * 100;  
    if(flag == 1)  
        ans = ans * 1.5;  
    if((s[len-1] - '0') % 2 == 0)  
        ans = ans * 2;  
    printf("%.2f%%", ans);  
    return 0;  
}