leetcode - Search for a Range

Given a sorted array of integers, find the starting and ending position of a given target value.

Your algorithm's runtime complexity must be in the order of O(log n).

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

For example,
Given [5, 7, 7, 8, 8, 10] and target value 8,
return [3, 4].

class Solution {public:    std::vector<int> searchRange(int A[], int n, int target) {std::vector<int> vec;int i;int cnt = 0;bool t = true;for (i = 0; i < n; i++){if(A[i] == target){cnt++;t = false;}else if(!t){break;}}if(cnt == 0){vec.push_back(-1);vec.push_back(-1);return vec;}else{vec.push_back(i-cnt);vec.push_back(i-1);return vec;}    }};