Submission #1986237

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Source Code Expand

#include <iostream>
#include <string>
#include <vector>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <algorithm>
#include <bitset>
#include <cstdio>
#include <cstdlib>
#include <cmath>
using namespace std;

using ll = long long;
using P = pair<int, int>;

const int INF = 1e9;
const int MOD = 1e9 + 7;

// 4近傍、8近傍
int dx[] = {1, 0, -1, 0, 1, -1, -1, 1};
int dy[] = {0, 1, 0, -1, 1, 1, -1, -1};

int main() {
  // 入力
  int r1, r2;
  cin >> r1 >> r2;

  // 解答
  printf("%.8f\n", (double)(r1 * r2) / (r1 + r2));

  return 0;
}

Submission Info

Judge Result