Find K-th Smallest Pair Distance LeetCode solution in C++

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class Solution {
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 public:
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  int count(vector<int> &temp, int mid) {
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    int i = 0, j = 0, n = temp.size();
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    int len = 0;
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    while (i < n) {
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      while (j < n && (temp[j] - temp[i]) <= mid) j++;
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      len += j - i - 1;
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      i++;
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    }
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    return len;
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  }
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  int smallestDistancePair(vector<int> &nums, int k) {
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    int s = 0, e = 1e6;
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    int ans = 0;
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    vector<int> temp = nums;
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    sort(temp.begin(), temp.end());
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    while (s <= e) {
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      int mid = s + (e - s) / 2;
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      if (count(temp, mid) >= k) {
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        ans = mid;
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        e = mid - 1;
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      } else {
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        s = mid + 1;
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      }
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    }
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    return ans;
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  }
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};