LeetCode [418] Sentence Screen Fitting

 418. Sentence Screen Fitting

Medium

Given a rows x cols screen and a sentence represented by a list of non-empty words, find how many times the given sentence can be fitted on the screen.

Note:

1. A word cannot be split into two lines.
2. The order of words in the sentence must remain unchanged.
3. Two consecutive words in a line must be separated by a single space.
4. Total words in the sentence won't exceed 100.
5. Length of each word is greater than 0 and won't exceed 10.
6. 1 ≤ rows, cols ≤ 20,000.

Example 1:

Input:
rows = 2, cols = 8, sentence = ["hello", "world"]

Output: 
1

Explanation:
hello---
world---

The character '-' signifies an empty space on the screen.

Example 2:

Input:
rows = 3, cols = 6, sentence = ["a", "bcd", "e"]

Output: 
2

Explanation:
a-bcd- 
e-a---
bcd-e-

The character '-' signifies an empty space on the screen.

Example 3:

Input:
rows = 4, cols = 5, sentence = ["I", "had", "apple", "pie"]

Output: 
1

Explanation:
I-had
apple
pie-I
had--

The character '-' signifies an empty space on the screen.

https://leetcode.com/problems/sentence-screen-fitting/discuss/90845/21ms-18-lines-Java-solution

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public class Solution { public int wordsTyping(String[] sentence, int rows, int cols) { String s = String.join(" ", sentence) + " "; int start = 0, l = s.length(); for (int i = 0; i < rows; i++) { start += cols; if (s.charAt(start % l) == ' ') { start++; } else { while (start > 0 && s.charAt((start-1) % l) != ' ') { start--; } } } return start / s.length(); } }