算法小练习题(0) 答案

上期毛毛虫问题的答案:

def find_slim_segments(widths: list):    
    slim_locations = []
    temp = []
    last_is_low = False
    for i in range(1, len(widths)):
        if widths[i] < widths[i - 1]:
            temp = []
            temp.append(i)
            last_is_low = True
        elif widths[i] == widths[i - 1]:
            if last_is_low:
                temp.append(i)
        else:
            if len(temp) > 0:
                slim_locations.append(temp)
                temp = []
            last_is_low = False
    return slim_locations

这个小算法可以用于图像分割。如下图，各斑块儿之间有桥接，连通域算法不奏效。这个简单算法反而可以分割它。

分割结果展示：

以下是为了凑字数

[21, 23, 23, 23, 21, 20, 24, 22, 23, 24, 23, 23, 22, 23, 22, 21, 22, 21, 21, 22, 24, 21, 21, 20, 24, 20, 20, 23, 21, 24, 24, 24, 21, 22, 21, 23, 24, 20, 23, 23, 24, 22, 21, 21, 24, 20, 21, 20, 23, 21]

[[5], [7], [12], [15], [17, 18], [23], [25, 26], [28], [32], [34], [37], [42, 43], [45], [47]]

[21, 23, 20, 21, 20, 20, 21, 23, 22, 21, 21, 23, 22, 24, 20, 22, 22, 22, 22, 22, 22, 20, 23, 23, 21, 22, 24, 21, 22, 23, 23, 21, 20, 22, 24, 21, 21, 20, 21, 23, 22, 23, 23, 23, 21, 24, 23, 23, 23, 20]

[[2], [4, 5], [9, 10], [12], [14], [21], [24], [27], [32], [37], [40], [44]]

[23, 21, 21, 24, 24, 20, 20, 23, 24, 24, 20, 21, 20, 21, 22, 24, 21, 20, 22, 24, 24, 24, 22, 24, 21, 22, 24, 22, 21, 21, 24, 23, 23, 21, 23, 24, 23, 20, 23, 23, 20, 20, 24, 24, 21, 22, 24, 21, 23, 24]

[[1, 2], [5, 6], [10], [12], [17], [22], [24], [28, 29], [33], [37], [40, 41], [44], [47]]