Find First and Last Position of Element in Sorted Array LeetCode solution in C++

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class Solution {
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 public:
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  int startEle(vector<int> &nums, int target, int l, int r) {
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    while (l <= r) {
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      int m = (l + r) / 2;
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      if (nums[m] < target)
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        l = m + 1;
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      else if (nums[m] > target)
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        r = m - 1;
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      else {
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        if (m == 0)
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          return m;
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        else if (nums[m - 1] == target)
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          r = m - 1;
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        else
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          return m;
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      }
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    }
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    return -1;
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  }
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  int lastEle(vector<int> &nums, int target, int l, int r) {
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    while (l <= r) {
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      int m = (l + r) / 2;
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      if (nums[m] < target)
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        l = m + 1;
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      else if (nums[m] > target)
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        r = m - 1;
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      else {
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        if (m == nums.size() - 1)
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          return m;
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        else if (nums[m + 1] == target)
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          l = m + 1;
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        else
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          return m;
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      }
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    }
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    return -1;
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  }
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  vector<int> searchRange(vector<int> &nums, int target) {
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    vector<int> binSearch;
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    int a = startEle(nums, target, 0, nums.size() - 1);
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    if (a == -1) {
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      binSearch.push_back(-1);
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      binSearch.push_back(-1);
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      return binSearch;
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    } else {
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      binSearch.push_back(a);
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    }
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    int b = lastEle(nums, target, 0, nums.size() - 1);
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    binSearch.push_back(b);
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    return binSearch;
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  }
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};