#include <stdio.h> //先定义一个求三个数中最大值的函数 int max3(int x, int y, int z) { int max = x; if( max < y) max = y; if(max < z) max = z; return max; } int main() { int a, b, c; float m = 0; scanf("%d %d %d", &a, &b, &c); m = (float) max3(a+b, b, c) / (max3(a, b+c, c) + max3(a, b, b+c)); printf("%.2f\n", m); return 0; }