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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Example 1:
Input: nums = [5,7,7,8,8,10], target = 8
Output: [3,4]
Example 2:
Input: nums = [5,7,7,8,8,10], target = 6
Output: [-1,-1]
Example 3:
Input: nums = [], target = 0
Output: [-1,-1]
Constraints:
0 <= nums.length <= 105
-109 <= nums[i] <= 109
nums is a non-decreasing array.
-109 <= target <= 109
Solution
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vector<int> searchRange(vector<int>& nums, int target) {
int left = -1, right = -1;
for (int i = 0; i < nums.size(); i++) {
if (nums[i] == target) {
left = i;
right = left;
for (int j = left; j < nums.size() && nums[j] == target; j++) {
right = j;
}
break;
}
}
return {left, right};
}
