找到将赢得硬币游戏的玩家

给定N个硬币，任务是找到谁赢得了硬币游戏。
硬币游戏是一种游戏，其中每个玩家都从给定的N个硬币中挑选硬币，这样他就可以在一轮中选择1到5个硬币，并且游戏对于两个玩家都将继续。选择最后一个硬币的玩家将输掉比赛。
例子：

Input: N = 4
Output: First Player
Explanation:
Player 1 pick 3 coins and 
Player 2 pick last coin

Input: N = 7
Output: Second Player

方法：

• 因为玩家可以拿取从1到5(含)之间的硬币，如果一个玩家输了，这意味着他只有1个硬币，否则，他本可以比可用硬币少拿1个硬币，并迫使另一位玩家输掉。因此，现在我们考虑第二个玩家要赢的情况，这意味着第一个玩家只有一个硬币。
• 在N = 1时，第二位玩家将获胜；在N = 2到6之间，第一位玩家可以选择比N少1个硬币，并迫使第二位玩家输掉，因此将其丢弃；对于N = 7，第一位玩家可以选择硬币从1到5，这将留下6到2的硬币，然后第二个玩家可以选择1到5，而赢得第二个玩家将明智地少选择1个硬币，迫使第一枚硬币松动，所以基本上从1开始，所有数字差距为6(无论第一玩家选择什么，第二玩家将选择等于6的差额的硬币，而第一玩家选择的硬币)将成为第二玩家的获胜。
• 最后，我们只需要检查n是否为6 * c + 1形式，则第二位玩家将获胜，否则第一位玩家将获胜。

下面是上述方法的实现：

C++

// C++ program to find the player
// who wins the game
 
#include 
using namespace std;
 
// Function to check the
// wining player
void findWinner(int n)
{
    // As discussed in the
    // above approach
    if ((n - 1) % 6 == 0) {
        cout << "Second Player wins the game";
    }
    else {
        cout << "First Player wins the game";
    }
}
 
// Driver function
int main()
{
 
    int n = 7;
    findWinner(n);
}

Java

// Java program to find the player
// who wins the game
class GFG
{
 
// Function to check the
// wining player
static void findWinner(int n)
{
    // As discussed in the
    // above approach
    if ((n - 1) % 6 == 0)
    {
        System.out.println("Second Player wins the game");
    }
    else
    {
        System.out.println("First Player wins the game");
    }
}
 
// Driver Code
public static void main(String[] args)
{
    int n = 7;
    findWinner(n);
}
}
 
// This code is contributed by Rajput-Ji

Python3

# Python3 program to find the player
# who wins the game
 
# Function to check the
# wining player
def findWinner(n):
     
    # As discussed in the
    # above approach
    if ((n - 1) % 6 == 0):
        print("Second Player wins the game");
    else:
        print("First Player wins the game");
     
# Driver Code
if __name__ == '__main__':
    n = 7;
    findWinner(n);
 
# This code is contributed by 29AjayKumar

C#

// C# program to find the player
// who wins the game
 
using System;
 
class GFG
{
     
    // Function to check the
    // wining player
    static void findWinner(int n)
    {
        // As discussed in the
        // above approach
        if ((n - 1) % 6 == 0)
        {
            Console.WriteLine("Second Player wins the game");
        }
        else
        {
            Console.WriteLine("First Player wins the game");
        }
    }
     
    // Driver Code
    public static void Main()
    {
        int n = 7;
        findWinner(n);
    }
}
 
// This code is contributed by AnkitRai01

Javascript

 
// JavaScript program to find the player
// who wins the game
 
// Function to check the
// wining player
function findWinner(n)
{
    // As discussed in the
    // above approach
    if ((n - 1) % 6 == 0) {
        document.write("Second Player wins the game");
    }
    else {
        document.write("First Player wins the game");
    }
}
 
// Driver function
var n = 7;
findWinner(n);
 

输出：

Second Player wins the game

时间复杂度： $O(1)$