[C++] lower_bound, upper_bound

 

LeetCode 34. Find First and Last Position of Element in Sorted Array

https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/

Find First and Last Position of Element in Sorted Array - LeetCode

class Solution {
public:
    vector<int> searchRange(vector<int>& nums, int target) {
        if (nums.size() == 0) {
            return {-1, -1};
        }
        int i = lower_bound(nums.begin(), nums.end(), target) - nums.begin();
        int j = upper_bound(nums.begin(), nums.end(), target) - 1 - nums.begin();
        if (i < nums.size() && nums[i] == target) {
            return {i, j};
        }
        return {-1, -1};
    }
};