（Python3）题解 | 构造数独

import sys

def main():
    n, k = map(int, sys.stdin.readline().split())

    # 构造解：只在对角线上放 k，其余填 0（非负整数）
    arr = [[0] * n for _ in range(n)]
    for i in range(n):
        arr[i][i] = k

    # 输出矩阵
    for row in arr:
        print(' '.join(map(str, row)))

main()