字节跳动第三题2048AC代码

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[][] matrix = new int[4][4];
        for (int i = 0; i < 4; i++) {
            for (int j = 0; j < 4; j++) {
                matrix[i][j] = sc.nextInt();
            }
        }

        switch (n) {
            case 1:
                for (int j = 0; j < 4; j++) {
                    int temp = 0;
                    for (int i = 0; i < 4; i++) {
                        if (matrix[i][j] != 0) {
                            boolean flag = false;
                            for (int k = i + 1; k < 4; k++) {
                                if (matrix[k][j] != 0) {
                                    if (matrix[i][j] == matrix[k][j]) {
                                        int ans = matrix[k][j] + matrix[i][j];
                                        matrix[i][j] = matrix[k][j] = 0;
                                        matrix[temp++][j] = ans;
                                        flag = true;
                                    }
                                    break;
                                }
                            }
                            if (!flag) {
                                int ans = matrix[i][j];
                                matrix[i][j] = 0;
                                matrix[temp++][j] = ans;
                            }
                        }
                    }
                }
                break;
            case 2:

                for (int j = 0; j < 4; j++) {
                    int temp = 3;
                    for (int i = 3; i >= 0; i--) {
                        if (matrix[i][j] != 0) {
                            boolean flag = false;
                            for (int k = i - 1; k >= 0; k--) {
                                if (matrix[k][j] != 0) {
                                    if (matrix[i][j] == matrix[k][j]) {
                                        int ans = matrix[k][j] + matrix[i][j];
                                        matrix[i][j] = matrix[k][j] = 0;
                                        matrix[temp--][j] = ans;
                                        flag = true;
                                    }
                                    break;
                                }
                            }
                            if (!flag) {
                                int ans = matrix[i][j];
                                matrix[i][j] = 0;
                                matrix[temp--][j] = ans;
                            }
                        }
                    }
                }
                break;
            case 3:
                for (int i = 0; i < 4; i++) {
                    int temp = 0;
                    for (int j = 0; j < 4; j++) {
                        if (matrix[i][j] != 0) {
                            boolean flag = false;
                            for (int k = j + 1; k < 4; k++) {
                                if (matrix[i][k] != 0) {
                                    if (matrix[i][j] == matrix[i][k]) {
                                        int ans = matrix[i][k] + matrix[i][j];
                                        matrix[i][j] = matrix[i][k] = 0;
                                        matrix[i][temp++] = ans;
                                        flag = true;
                                    }

                                    break;
                                }
                            }
                            if (!flag) {
                                int ans = matrix[i][j];
                                matrix[i][j] = 0;
                                matrix[i][temp++] = ans;
                            }
                        }
                    }
                }
                break;
            case 4:
                for (int i = 0; i < 4; i++) {
                    int temp = 3;
                    for (int j = 3; j >= 0; j--) {
                        if (matrix[i][j] != 0) {
                            boolean flag = false;
                            for (int k = j - 1; k >= 0; k--) {
                                if (matrix[i][k] != 0) {
                                    if (matrix[i][j] == matrix[i][k]) {
                                        int ans = matrix[i][k] + matrix[i][j];
                                        matrix[i][j] = matrix[i][k] = 0;
                                        matrix[i][temp--] = ans;
                                        flag = true;
                                    }
                                    break;
                                }
                            }
                            if (!flag) {
                                int ans = matrix[i][j];
                                matrix[i][j] = 0;
                                matrix[i][temp--] = ans;
                            }
                        }
                    }
                }
                break;
        }

        for (int i = 0; i < 4; i++) {
            for (int j = 0; j < 4; j++) {
                if (j != 0) {
                    System.out.print(" ");
                }
                System.out.print(matrix[i][j]);
            }
            System.out.println();
        }
    }

}