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Java-based LeetCode algorithm problem solutions, regularly updated

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package g0401_0500.s0486_predict_the_winner;

// #Medium #Array #Dynamic_Programming #Math #Recursion #Game_Theory
// #2022_07_21_Time_1_ms_(85.17%)_Space_42_MB_(17.19%)

/**
 * 486 - Predict the Winner\.
 *
 * Medium
 *
 * You are given an integer array `nums`. Two players are playing a game with this array: player 1 and player 2.
 *
 * Player 1 and player 2 take turns, with player 1 starting first. Both players start the game with a score of `0`. At each turn, the player takes one of the numbers from either end of the array (i.e., `nums[0]` or `nums[nums.length - 1]`) which reduces the size of the array by `1`. The player adds the chosen number to their score. The game ends when there are no more elements in the array.
 *
 * Return `true` if Player 1 can win the game. If the scores of both players are equal, then player 1 is still the winner, and you should also return `true`. You may assume that both players are playing optimally.
 *
 * **Example 1:**
 *
 * **Input:** nums = [1,5,2]
 *
 * **Output:** false
 *
 * **Explanation:** Initially, player 1 can choose between 1 and 2. If he chooses 2 (or 1), then player 2 can choose from 1 (or 2) and 5. If player 2 chooses 5, then player 1 will be left with 1 (or 2). So, final score of player 1 is 1 + 2 = 3, and player 2 is 5. Hence, player 1 will never be the winner and you need to return false.
 *
 * **Example 2:**
 *
 * **Input:** nums = [1,5,233,7]
 *
 * **Output:** true
 *
 * **Explanation:** Player 1 first chooses 1. Then player 2 has to choose between 5 and 7. No matter which number player 2 choose, player 1 can choose 233. Finally, player 1 has more score (234) than player 2 (12), so you need to return True representing player1 can win.
 *
 * **Constraints:**
 *
 * *   `1 <= nums.length <= 20`
 * *   0 <= nums[i] <= 10⁷
**/
@SuppressWarnings("java:S3012")
public class Solution {
    public boolean predictTheWinner(int[] nums) {
        int n = nums.length;
        int[][] dp = new int[n][n];
        for (int i = 0; i < n; i++) {
            dp[i][i] = nums[i];
        }
        for (int len = 1; len < n; len++) {
            for (int i = 0; i < n - len; i++) {
                int j = i + len;
                dp[i][j] = Math.max(nums[i] - dp[i + 1][j], nums[j] - dp[i][j - 1]);
            }
        }
        return dp[0][n - 1] >= 0;
    }
}