0292-nim-game.js

// 292. Nim Game
// Easy   55%


// 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.

// Credits:Special thanks to @jianchao.li.fighter for adding this problem and
// creating all test cases.


/**
 * @param {number} n
 * @return {boolean}
 */
const canWinNim = function(n) {
  return !!(n % 4)
}

;[
  4,                            // false
].forEach(n => {
  console.log(canWinNim(n))
})

// Solution:
// 如果是 4 的倍数，就不可能赢。

// Submission Result: Accepted