2260. Minimum Consecutive Cards to Pick Up Medium

1use std::collections::HashMap;
2
3/**
4 * [2260] Minimum Consecutive Cards to Pick Up
5 *
6 * You are given an integer array cards where cards[i] represents the value of the i^th card. A pair of cards are matching if the cards have the same value.
7 * Return the minimum number of consecutive cards you have to pick up to have a pair of matching cards among the picked cards. If it is impossible to have matching cards, return -1.
8 *  
9 * Example 1:
10 *
11 * Input: cards = [3,4,2,3,4,7]
12 * Output: 4
13 * Explanation: We can pick up the cards [3,4,2,3] which contain a matching pair of cards with value 3. Note that picking up the cards [4,2,3,4] is also optimal.
14 *
15 * Example 2:
16 *
17 * Input: cards = [1,0,5,3]
18 * Output: -1
19 * Explanation: There is no way to pick up a set of consecutive cards that contain a pair of matching cards.
20 *
21 *  
22 * Constraints:
23 *
24 * 1 <= cards.length <= 10^5
25 * 0 <= cards[i] <= 10^6
26 *
27 */
28pub struct Solution {}
29
30// problem: https://leetcode.com/problems/minimum-consecutive-cards-to-pick-up/
31// discuss: https://leetcode.com/problems/minimum-consecutive-cards-to-pick-up/discuss/?currentPage=1&orderBy=most_votes&query=
32
33// submission codes start here
34
35impl Solution {
36    pub fn minimum_card_pickup(cards: Vec<i32>) -> i32 {
37        let mut map: HashMap<i32, usize> = HashMap::new();
38        let mut ans: i32 = i32::MAX;
39        for i in 0..cards.len() {
40            let current: i32 = match map.get(&cards[i]) {
41                None => i32::MAX,
42                Some(last) => (i - *last + 1) as i32,
43            };
44
45            if current < ans {
46                ans = current;
47            }
48
49            map.insert(cards[i], i);
50        }
51
52        if ans == i32::MAX {
53            -1
54        } else {
55            ans
56        }
57    }
58}
59
60// submission codes end
61
62#[cfg(test)]
63mod tests {
64    use super::*;
65
66    #[test]
67    fn test_2260_1() {
68        assert_eq!(Solution::minimum_card_pickup(vec!(3, 4, 2, 3, 4, 7)), 4);
69        assert_eq!(Solution::minimum_card_pickup(vec!(1, 0, 5, 3)), -1);
70
71        assert_eq!(
72            Solution::minimum_card_pickup(vec!(
73                70, 37, 70, 41, 1, 62, 71, 49, 38, 50, 29, 76, 29, 41, 22, 66, 88, 18, 85, 53
74            )),
75            3
76        );
77    }
78}
79