uva 10491

https://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1432

#include <stdio.h>

int main () {
    int a, b, c;
    while (scanf("%d%d%d", &a, &b, &c) == ) {
        printf("%.5lf\n", (1.0 * a * b + b * (b - )) / (a + b - c - ) / (a + b ));
    }
    return ;
}