#include <algorithm>
#include <array>
#include <cmath>
#include <cstdio>
#include <deque>
#include <iomanip>
#include <iostream>
#include <numeric>
#include <optional>
#include <queue>
#include <set>
#include <stack>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

int main() {
    double max_x = 0, sum = 0;
    for (auto i = 0; i < 3; ++i) {
        double x;
        cin >> x;
        sum += x;
        max_x = max(max_x, x);
    }
    printf("%.12f\n", max_x / sum);
    return 0;
}