// SelectNth select n-th (n start by 1) order statistic from the input array,
// return the index of the n-th element if succeed, -1 if failed.
SelectNth select n-th (n start by 1) order statistic from the input array,
return the index of the n-th element if succeed, -1 if failed.
// SelectNth select n - th ( n start by 1 ) order statistic from the input array // return the index of the n - th element if succeed - 1 if failed .
func SelectNth(in []int, n int) int {
	if n <= 0 || n > len(in) {
		return -1
	}
	return selectNthImpl(subArray(in), n-1, 0, len(in)-1)
}
func SelectNth ( in [ ] int , n int ) int { if n <= 0 || n > len ( in ) { return - 1 } return selectNthImpl ( subArray ( in ) , n - 1 , 0 , len ( in ) - 1 ) }
SelectNth select n-th (n start by 1) order statistic from the input array,
return the index of the n-th element if succeed, -1 if failed.
SelectNth select n - th ( n start by 1 ) order statistic from the input array return the index of the n - th element if succeed - 1 if failed .