def partition(A, p, r):    j = p+1    for i in range(p+1, r+1):        if(A[i] < A[p]):            tmp = A[i]            A[i] = A[j]            A[j] = tmp            j = j + 1    tmp = A[p]    A[p] = A[j-1]    A[j-1] = tmp    return j - 1   def select(A, p, r, i):    if(p == r):        return A[p]    q = partition(A, p, r)    #print q    k = q - p + 1    if(k == i):        return A[q]    if(i < k):        return select(A, p, q - 1, i)    else:        return select(A, q + 1, r, i - k)#test case#import pdb#pdb.set_trace()old = [2, 5, 3, 0, 7, 9, 6, 3]     q = select(old, 0, 7, 6)print q