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| class Solution {
int n = 100010;
int[][] st = new int[n][26];
int[] count = new int[n];
int idx = 0;
Map<String, Integer> map = new HashMap<>();
public List<String> topKFrequent(String[] words, int k) {
for (String str : words) {
insert(str);
}
PriorityQueue<String> queue = new PriorityQueue<>(k, (o1,o2)->{
if (map.get(o2) == map.get(o1)){
return o1.compareTo(o2);
}
return map.get(o2) - map.get(o1);
});
for (String str : words) {
int cnt = search(str);
map.put(str, cnt);
if (!queue.contains(str)) {
queue.offer(str);
}
}
List<String> res = new ArrayList<>();
while (k > 0){
res.add(queue.poll());
k--;
}
return res;
}
public void insert(String str){
int p = 0;
for (int i = 0; i < str.length(); i++) {
int j = str.charAt(i) - 'a';
if (st[p][j] == 0) {
st[p][j] = ++idx;
}
p = st[p][j];
}
count[p]++;
}
public int search(String str){
int p = 0;
for (int i = 0; i < str.length(); i++) {
int j = str.charAt(i) - 'a';
if (st[p][j] == 0) {
return 0;
}
p = st[p][j];
}
return count[p];
}
}
|
