Search For Range

• Time : O(logn)
• Space : O(1)

#include <vector>
using namespace std;

int minIndex(vector<int>& A, int& t) {
	int l = 0, r = A.size() - 1, res = INT_MAX;
	while(l <= r) {
		int m = (l + r) / 2;
		if(A[m] == t) res = min(res, m);
		if(A[m] >= t) r = m - 1;
		else l = m + 1;
	}
	if(res == INT_MAX or A[res] != t) return -1;
	return res;
}

int maxIndex(vector<int>& A, int& t) {
	int l = 0, r = A.size() - 1, res = -1;
	while(l <= r) {
		int m = (l + r) / 2;
		if(A[m] == t) res = max(res, m);
		if(A[m] <= t) l = m + 1;
		else r = m - 1;
	}
	if(res == -1 or A[res] != t) return -1;
	return res;
}

vector<int> searchForRange(vector<int> array, int target) {
  // Write your code here.
  return {minIndex(array, target), maxIndex(array, target)};
}