打印螺旋矩阵

打印螺旋矩阵3.py

def main(n):
    delta = [(1,0), (0,1), (-1,0), (0,-1)]
    arr = [[0 for _ in range(n)] for _ in range(n)]
    row,col,k,di = -1,0,1,0
    while k <= n*n:
        row += delta[di][0]
        col += delta[di][1]
        if not 0 <= row < n or not 0 <= col < n or arr[row][col] > 0:
            row -= delta[di][0]
            col -= delta[di][1]
            di = (di + 1) % len(delta)
            row += delta[di][0]
            col += delta[di][1]
        arr[row][col] = k
        k += 1

    for row in arr:
        print(' '.join(f"{x}" for x in row))
        
        
def main2(n):
    a = [[0 for _ in range(n)] for _ in range(n)]

    dir = ((0, 1), (1, 0), (0, -1), (-1, 0))
    r, c = 0, 0
    i = 0
    k = 1
    while k <= n*n:
        if a[r][c] == 0:
            a[r][c] = k
            k += 1
        nr = r + dir[i][0]
        nc = c + dir[i][1]
        if 0 <= nr < n and 0 <= nc < n and a[nr][nc] == 0:
            r, c = nr, nc
        else:
            i = (i+1) % 4

    for r in a:
        print(r)

        
if __name__ == '__main__':
    main(9)
    main2(9)