打印沙漏

def solve(n, c):
    n, c = int(n), str(c).strip()
    # 找最大奇数k使得k^2 <= n
    k = 1
    while (k + 2) ** 2 <= n:
        k += 2
    rows = []
    w = k
    while w >= 1:
        spaces = ' ' * ((k - w) // 2)
        rows.append(spaces + c * w)
        w -= 2
    w = 3
    while w <= k:
        spaces = ' ' * ((k - w) // 2)
        rows.append(spaces + c * w)
        w += 2
    for row in rows:
        print(row)
    print(n - k * k)