#include <stdio.h>

int main(void)
{
    int hyou[100];
    int n = fgetc(stdin);
    int i, border;
    int total = 0;
    int answer = 0;
    
    for(i = 0; i < n; i++){
        hyou[i] = fgetc(stdin);
        total += hyou[i];
    }
    
    border = total / 10;
    for(i = 0; i < n; i++){
        if(hyou[i] <= border){
            answer++;
        }
    }
    
    printf("%d\n", answer * 30);
    
    return 0;
}