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class Solution {
public:
    void bSearch(int A[],int left,int right,int target,int flag,int &val) {
        if(left > right) return;
        int mid = (left + right) / 2;
        if(A[mid] == target) {
            val = mid;
            if(flag == 0) {
                bSearch(A, left, mid-1, target, flag, val);
            } else {
                bSearch(A, mid+1, right, target, flag, val);
            }
        } else {
            if(A[mid] < target) {
                bSearch(A, mid+1, right, target, flag, val);
            } else {
                bSearch(A, left, mid-1, target, flag, val);
            }
        }
    }

    vector<int> searchRange(int A[], int n, int target) {
        vector<int> ans;
        ans.clear();
        int left = -1;
        int right = -1;
        bSearch(A, 0, n-1, target, 0, left);
        bSearch(A, 0, n-1, target, 1, right);
        ans.push_back(left);
        ans.push_back(right);
        return ans;
    }
};