Binary Search

//thuat toan tim kiem nhi phan
int Binary(int* a, int n, int x)
{
    int left = 0;
    int right = n-1;
    int mid;
    while ( left <= right)
    {
        mid =( left + right ) / 2;
        if ( x < a[mid] )
            right = mid - 1;
        else if ( x > a[mid] )
            left = mid + 1;
        else
            return mid;
    }
    return -1;
}