原题链接
代码如下:
class Solution {
public:
bool containsNearbyDuplicate(vector<int>& nums, int k) {
unordered_map<int, int> hash;
for(int i = 0; i < nums.size(); i ++){
if(hash.count(nums[i])){
int m = i - hash[nums[i]];
if(m <= k) return true;
}
hash[nums[i]] = i;
}
return false;
}
};