1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57

#![allow(clippy::needless_range_loop)]
/// 剑指 Offer 48. 最长不含重复字符的子字符串
/// <https://leetcode.cn/problems/zui-chang-bu-han-zhong-fu-zi-fu-de-zi-zi-fu-chuan-lcof/>
use std::collections::HashMap;

pub struct Solution;

#[allow(unused)]
impl Solution {
	// 双指针 + hash
	// https://leetcode.cn/problems/zui-chang-bu-han-zhong-fu-zi-fu-de-zi-zi-fu-chuan-lcof/solution/mian-shi-ti-48-zui-chang-bu-han-zhong-fu-zi-fu-d-9/
	pub fn length_of_longest_substring(s: String) -> i32 {
		let mut ans = 0;
		let mut dict = HashMap::new();
		let len = s.len();
		let v = s.chars().collect::<Vec<char>>();
		let mut j = -1;

		for i in 0..len {
			if dict.contains_key(&v[i]) {
				j = (*dict.get(&v[i]).unwrap() as i32).max(j)
			}

			dict.insert(v[i], i);

			ans = ans.max(i as i32 - j);
		}

		ans
	}
}

#[cfg(test)]
mod tests {
	use super::*;

	#[test]
	fn test() {
		assert_eq!(Solution::length_of_longest_substring("abcabcbb".to_string()), 3);
		assert_eq!(Solution::length_of_longest_substring("bbbbb".to_string()), 1);
		assert_eq!(Solution::length_of_longest_substring("pwwkew".to_string()), 3);
		assert_eq!(Solution::length_of_longest_substring("".to_string()), 0);
		assert_eq!(Solution::length_of_longest_substring("au".to_string()), 2);
		assert_eq!(Solution::length_of_longest_substring("dvdf".to_string()), 3);
		assert_eq!(Solution::length_of_longest_substring("abba".to_string()), 2);
		assert_eq!(Solution::length_of_longest_substring("aab".to_string()), 2);
		assert_eq!(Solution::length_of_longest_substring("abcabcbb".to_string()), 3);
		assert_eq!(Solution::length_of_longest_substring("bbbbb".to_string()), 1);
		assert_eq!(Solution::length_of_longest_substring("pwwkew".to_string()), 3);
		assert_eq!(Solution::length_of_longest_substring("".to_string()), 0);
		assert_eq!(Solution::length_of_longest_substring("au".to_string()), 2);
		assert_eq!(Solution::length_of_longest_substring("dvdf".to_string()), 3);
		assert_eq!(Solution::length_of_longest_substring("abba".to_string()), 2);
		assert_eq!(Solution::length_of_longest_substring("aab".to_string()), 2);
		assert_eq!(Solution::length_of_longest_substring("abcabcbb".to_string()), 3);
	}
}