### Day 1 | Binary Search

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

Given an array of integers nums sorted in non-decreasing order, find the starting and ending position of a given target value.

If target is not found in the array, return [-1, -1].

You must write an algorithm with O(log n) runtime complexity.

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class Solution {
public:
vector<int> searchRange(vector<int>& nums, int target) {
int len(nums.size()), first = -1, last = -1;
int l(0), r(len-1);
while(l<=r){
int mid = l + (r - l)/2;
if(nums[mid] == target)
first = mid;
if(nums[mid] >= target)
r = mid - 1;
else
l = mid + 1;
}
l = 0, r = len-1;
while(l<=r){
int mid = l + (r - l)/2;
if(nums[mid] == target)
last = mid;
if(nums[mid] > target)
r = mid -1;
else
l = mid + 1;
}
return {first, last};
}
};