# 2107. Number of Unique Flavors After Sharing K Candies
###### tags: `Leetcode` `Medium` `Sliding Window`
Link: https://leetcode.com/problems/number-of-unique-flavors-after-sharing-k-candies/description/
## 思路

sliding window 把window里面的元素的cnt从```cnt```里面减下去
那么如果把window里面的candy给sister 自己的unique flavors就是```cnt.size()```
## Code

class Solution {
public int shareCandies(int[] candies, int k) {
Map<Integer, Integer> cnt = new HashMap<>();
for(int candy:candies){
cnt.put(candy, cnt.getOrDefault(candy, 0)+1);
}
int ans = 0;
for(int i=0; i<candies.length; i++){
if(i>=k){
cnt.put(candies[i-k], cnt.getOrDefault(candies[i-k], 0)+1);
}
cnt.put(candies[i], cnt.getOrDefault(candies[i], 0)-1);
if(cnt.get(candies[i])==0) cnt.remove(candies[i]);
if(i>=k-1) ans = Math.max(ans, cnt.size());
}
return ans;
}
}