LeetCode 806 Number of Lines To Write String 解题报告

题目要求

We are to write the letters of a given string S, from left to right into lines. Each line has maximum width 100 units, and if writing a letter would cause the width of the line to exceed 100 units, it is written on the next line. We are given an array widths, an array where widths[0] is the width of 'a', widths[1] is the width of 'b', ..., and widths[25] is the width of 'z'.

Now answer two questions: how many lines have at least one character from S, and what is the width used by the last such line? Return your answer as an integer list of length 2.

题目分析及思路

题目给出一个字符串和每个字母的长度数组，且限制每一行的最大值是100个单位，要求得到最后的行数和最后一行的宽度。可以遍历该字符串，每100个单位判断一下。

python代码

class Solution:

    def numberOfLines(self, widths: 'List[int]', S: 'str') -> 'List[int]':

        lines, width = 1, 0

        for s in S:

            w = widths[ord(s) - ord('a')]

            width += w

            if width > 100:

                lines += 1

                width = w

        return [lines, width]