独角兽公司电话面试 Coding 题目的解答 2019-June

前提假设是 两边 边界, 有无穷高的墙.

这里是完整的代码和输出示例.

# Time: max(A) * len(A)
# Space: O(1)

def fill_slot(B, curt):
    if not B:
        return
    n = len(B)
    i = curt
    while i > 0 and B[i - 1] <= B[i]:
        i -= 1
    left, left_low = i, B[i]
    i = curt
    while i < n - 1 and B[i + 1] <= B[i]:
        i += 1
    right, right_low = i, B[i]
    if left_low <= right_low:
        B[left] += 1
        return
    B[right] += 1

def print_hist(A, position, qty):
    B = A[:]
    print(A)
    for _ in range(qty):
        fill_slot(B, position)
        print(B)
    
    height = max(B)
    n = len(B)
    for h in range(height, 0, -1):
        line = []
        for i in range(n):
            if h > B[i]:
                line.append(" ")
                print(" ", end = " ")
            elif A[i] < h <= B[i]:
                line.append("o")
                print("o", end = " ")
            elif h <= A[i]:
                line.append("x")
                print("x", end = " ")
        print("", end = "
")
        # print(" ".join(line))
    print(" ".join([str(i) for i in range(n)]))

A = [7,1,3,1,0,4,1,0]
print_hist(A, 5, 4)
print_hist(A, 5, 9)
print_hist(A, 4, 9)

输出 - print_hist(A, 5, 4)

[7, 1, 3, 1, 0, 4, 1, 0]
[7, 1, 3, 1, 1, 4, 1, 0]
[7, 1, 3, 1, 1, 4, 1, 1]
[7, 1, 3, 2, 1, 4, 1, 1]
[7, 1, 3, 2, 2, 4, 1, 1]


x
x
x
x         x
x   x     x
x   x o o x
x x x x o x x o

0 1 2 3 4 5 6 7

输出 - print_hist(A, 5, 9)

[7, 1, 3, 1, 0, 4, 1, 0]
[7, 1, 3, 1, 1, 4, 1, 0]
[7, 1, 3, 1, 1, 4, 1, 1]
[7, 1, 3, 2, 1, 4, 1, 1]
[7, 1, 3, 2, 2, 4, 1, 1]
[7, 1, 3, 2, 2, 4, 1, 2]
[7, 1, 3, 2, 2, 4, 2, 2]
[7, 1, 3, 3, 2, 4, 2, 2]
[7, 1, 3, 3, 3, 4, 2, 2]
[7, 2, 3, 3, 3, 4, 2, 2]

x
x
x
x         x
x   x o o x
x o x o o x o o
x x x x o x x o

0 1 2 3 4 5 6 7

print_hist(A, 4, 9)

[7, 1, 3, 1, 0, 4, 1, 0]
[7, 1, 3, 1, 1, 4, 1, 0]
[7, 1, 3, 2, 1, 4, 1, 0]
[7, 1, 3, 2, 2, 4, 1, 0]
[7, 1, 3, 3, 2, 4, 1, 0]
[7, 1, 3, 3, 3, 4, 1, 0]
[7, 2, 3, 3, 3, 4, 1, 0]
[7, 3, 3, 3, 3, 4, 1, 0]
[7, 4, 3, 3, 3, 4, 1, 0]
[7, 4, 4, 3, 3, 4, 1, 0]

x
x
x
x o o     x
x o x o o x
x o x o o x
x x x x o x x

0 1 2 3 4 5 6 7