[C#][LeetCode][Easy] 292. Nim Game

心得：

一次可以拿1~3顆石頭，最後一個把石頭拿完的人就算勝利，很簡單的一支小程式判斷是否可以贏得這場遊戲，而且有先手優勢，所以只要是除不滿4就一定會贏。

問題：

You are playing the following Nim Game with your friend: There is a heap of stones on the table, each time one of you take turns to remove 1 to 3 stones. The one who removes the last stone will be the winner. You will take the first turn to remove the stones.

Both of you are very clever and have optimal strategies for the game. Write a function to determine whether you can win the game given the number of stones in the heap.

For example, if there are 4 stones in the heap, then you will never win the game: no matter 1, 2, or 3 stones you remove, the last stone will always be removed by your friend.

Hint:

If there are 5 stones in the heap, could you figure out a way to remove the stones such that you will always be the winner?

答案：

public class Solution {
    public bool CanWinNim(int n) {
        if(n < 4){
            return true;
        }
        else{
            return n % 4 > 0;
        }
    }
}