README.md

2260. Minimum Consecutive Cards to Pick Up

You are given an integer array cards where cards[i] represents the value of the ith card. A pair of cards are matching if the cards have the same value.

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.

Example 1:

Input: cards = [3,4,2,3,4,7]
Output: 4
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.

Example 2:

Input: cards = [1,0,5,3]
Output: -1
Explanation: There is no way to pick up a set of consecutive cards that contain a pair of matching cards.

Constraints:

• 1 <= cards.length <= 105
• 0 <= cards[i] <= 106

Solutions (Rust)

1. Solution

use std::collections::HashMap;

impl Solution {
    pub fn minimum_card_pickup(cards: Vec<i32>) -> i32 {
        let mut indices = HashMap::new();
        let mut ret = usize::MAX;

        for i in 0..cards.len() {
            if let Some(j) = indices.insert(cards[i], i) {
                ret = ret.min(i - j + 1);
            }
        }

        if ret == usize::MAX {
            return -1;
        }

        ret as i32
    }
}