I used C++, but got Compile error...
Succeed when using G++, code:

#include <stdio.h>

main(){
    double in,sum=0;
    int i;
    for(i=0;i<12;i++){
        scanf("%lf",&in);
        sum+=in;
    }
    printf("$%.2f",sum/12);
    return 0;
}


It's quite confusing that... If I use printf("lf") rather than printf("f"), I'll get a WA...