Description
Given an array of integers and an integer k, find out whether there are two distinct indices i and j in the array such that nums[i] = nums[j] and the absolute difference between i and j is at most k.
Solution
HashMap
class Solution {
public boolean containsNearbyDuplicate(int[] nums, int k) {
Map<Integer, Integer> numToIndice = new HashMap<>();
for (int i = 0; i < nums.length; ++i) {
int num = nums[i];
if (numToIndice.containsKey(num)
&& i - numToIndice.get(num) <= k) {
return true;
}
numToIndice.put(num, i);
}
return false;
}
}
