#include <stdio.h> double three_max(double x, double y, double z); int main() { double a = 0; double b = 0; double c = 0; scanf("%lf %lf %lf", &a, &b, &c); // 分母 double deno = three_max(a, b + c, c) + three_max(a, b, b + c); // 分子 double mol = three_max(a + b, b, c);...