Medium
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
import java.util.HashMap;
import java.util.Map;
public class Solution {
public int minimumCardPickup(int[] cards) {
int mindiff = Integer.MAX_VALUE;
Map<Integer, Integer> map = new HashMap<>();
int n = cards.length;
for (int i = 0; i < n; i++) {
if (map.containsKey(cards[i])) {
int j = map.get(cards[i]);
mindiff = Math.min(mindiff, i - j + 1);
}
map.put(cards[i], i);
}
if (mindiff == Integer.MAX_VALUE) {
return -1;
}
return mindiff;
}
}