LeetCode-5:蜡烛之间的盘子

Posted 2022-03-09 il_持之以恒_li

原题为：

参考代码为：

class Solution(object):
    def platesBetweenCandles(self, s, queries):
        """
        :type s: str
        :type queries: List[List[int]]
        :rtype: List[int]
        """
        n = len(s)
        list_1 = [0] * n
        list_2 = [0] * n  # 从后往前
        list_3 = [0] * n  # 从前往后
        if s[0] == '|':
            list_1[0] = 1
            list_3[0] = 0

        if s[n-1] == '|':
            list_2[n-1] = n-1

        for i in range(1, n):
            if s[i] == '|':
                list_1[i] = list_1[i - 1] + 1
            else:
                list_1[i] = list_1[i - 1]

            if s[i] == '|':
                list_3[i] = i
            else:
                list_3[i] = list_3[i-1]

        for i in range(n-2,-1,-1):
            if s[i] == '|':
                list_2[i] = i
            else:
                list_2[i] = list_2[i + 1]

        out = []
        for list_4 in queries:
            start = list_4[0]
            end = list_4[1]
            if start == end:
                out.append(0)
                continue

            index_1 = list_2[start]
            index_2 = list_3[end]
            if index_1 >=index_2:
                out.append(0)
            else:
                out.append(index_2-index_1+1-(list_1[index_2]-list_1[index_1]+1))

        return out

执行结果：