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class Solution {
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 public:
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  bool isPossible(vector<int> &nums) {
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    priority_queue<int, vector<int>, greater<int>> pq;
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    unordered_map<int, int> um;
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    for (int &num : nums) {
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      pq.push(num);
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      um[num]++;
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    }
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    queue<int> q;
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    int count = 0, prev;
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    while (!pq.empty()) {
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      if (count == 0) {
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        prev = pq.top();
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        pq.pop();
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        count++;
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      } else if (pq.top() == prev + 1) {
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        if (um[pq.top()] >= um[prev]) {
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          um[prev]--;
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          pq.pop();
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          prev += 1;
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          count++;
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        } else if (um[pq.top()] < um[prev]) {
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          um[prev]--;
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          if (count <= 2) return false;
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          while (!q.empty()) {
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            pq.push(q.front());
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            q.pop();
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          }
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          count = 0;
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        }
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      } else if (pq.top() == prev) {
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        q.push(pq.top());
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        pq.pop();
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        if (pq.empty()) {
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          if (count <= 2) return false;
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          while (!q.empty()) {
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            pq.push(q.front());
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            q.pop();
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          }
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          count = 0;
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        }
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      } else if (pq.top() > prev + 1) {
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        if (count <= 2) return false;
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        while (!q.empty()) {
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          pq.push(q.front());
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          q.pop();
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        }
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        count = 0;
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      }
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    }
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    if (count > 0 && count <= 2) return false;
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    return true;
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  }
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};