题解 | #蛇形矩阵#

import java.util.Scanner;

// 找规律没什么好说的
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextInt()) { // 注意 while 处理多个 case
            int lineNum = in.nextInt();
            int[][] ans = new int[lineNum][lineNum];
            for (int i = 0; i < lineNum; i++) {
                for (int j = 0; j < lineNum - i; j++) {
                    if (i == 0 && j == 0) {
                        ans[i][j] = 1;
                    } else if (j == 0) {
                        ans[i][j] = ans[i - 1][j] + i;
                    } else {
                        ans[i][j] = ans[i][j - 1] + j + 1 + i;
                    }
                }
            }
            for (int k = 0; k < lineNum; k++) {
                for (int l = 0; l < lineNum - k; l++) {
                    System.out.print(ans[k][l] + " ");
                }
                System.out.println();
            }
        }
    }
}