文章目录
一、题目
Given an integer array nums and an integer k, return true if there are two distinct indices i and j in the array such that nums[i] == nums[j] and abs(i - j) <= k.
Example 1:
Input: nums = [1,2,3,1], k = 3
Output: true
Example 2:
Input: nums = [1,0,1,1], k = 1
Output: true
Example 3:
Input: nums = [1,2,3,1,2,3], k = 2
Output: false
Constraints:
1 <= nums.length <= 105
-109 <= nums[i] <= 109
0 <= k <= 105
二、题解
cpp
class Solution {
public:
bool containsNearbyDuplicate(vector<int>& nums, int k) {
int n = nums.size();
unordered_map<int,int> map;
for(int i = 0;i < n;i++){
if(map.find(nums[i]) == map.end()) map[nums[i]] = i;
else{
if(abs(map[nums[i]] - i) <= k) return true;
map[nums[i]] = i;
}
}
return false;
}
};