Check if arr [ mid ] is the first occurrence of x . arr [ mid ] is first occurrence if x is one of the following is true : ( i ) mid == 0 and arr [ mid ] = = x ( ii ) arr [ mid - 1 ] < x and arr [ mid ] == x
if ( ( mid == 0 x > arr [ mid - 1 ] ) && ( arr [ mid ] == x ) ) return mid ; else if ( x > arr [ mid ] ) return _binarySearch ( arr , ( mid + 1 ) , high , x ) ; else return _binarySearch ( arr , low , ( mid - 1 ) , x ) ; } return - 1 ; }