原题链接：Leetcode 806. Number of Lines To Write String
You are given a string s of lowercase English letters and an array widths denoting how many pixels wide each lowercase English letter is. Specifically, widths[0] is the width of 'a', widths[1] is the width of 'b', and so on.
You are trying to write s across several lines, where each line is no longer than 100 pixels. Starting at the beginning of s, write as many letters on the first line such that the total width does not exceed 100 pixels. Then, from where you stopped in s, continue writing as many letters as you can on the second line. Continue this process until you have written all of s.
Return an array result of length 2 where:
result[0] is the total number of lines.
result[1] is the width of the last line in pixels.
Example 1:
Input: widths = [10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10], s = "abcdefghijklmnopqrstuvwxyz"
Output: [3,60]
Explanation: You can write s as follows:
abcdefghij // 100 pixels wide
klmnopqrst // 100 pixels wide
uvwxyz // 60 pixels wide
There are a total of 3 lines, and the last line is 60 pixels wide.
Example 2:
Input: widths = [4,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10], s = "bbbcccdddaaa"
Output: [2,4]
Explanation: You can write s as follows:
bbbcccdddaa // 98 pixels wide
a // 4 pixels wide
There are a total of 2 lines, and the last line is 4 pixels wide.
Constraints:
- widths.length == 26
- 2 <= widths[i] <= 10
- 1 <= s.length <= 1000
scontains only lowercase English letters.
方法一：模拟
思路：
直接模拟即可，lines从1开始，当res大于100时，新开一行。
注意： 同一个字母不能写到两行
c++代码：
class Solution {
public:
vector<int> numberOfLines(vector<int>& widths, string s) {
// lines行数 res最后一行的宽度
int lines = 1, res = 0;
for(auto c : s){
// 一个字母需要的长度
int need = widths[c - 'a'];
res += need;
if(res > 100){
lines++;
res = need;
}
}
return {lines, res};
}
};
复杂度分析：
- 时间复杂度：O(n) ，n为字符串长度
- 空间复杂度：O(1)
