Sorting Algorithms

Merge sort by using recursive strategy, i.e. divide and conquer.

def merge(left,right):
    result = []
    i,j =0,0
    while i < len(left) and j < len(right):
        if left[i]<right[j]:
            result.append(left[i])
            i +=1
        else:
            result.append(right[j])
            j +=1
    result += left[i:]
    result += right[j:]
    return result

def merge_Sort(seq):
    if len(seq)<=1:
        return seq
    mid = len(seq)/2
    left = merge_Sort(seq[:mid])
    right = merge_Sort(seq[mid:])
    return merge(left,right)

seq = [0, 1, 1, 3, 4, 5, 6, 7, 7, 12, 12, 26, 34, 42, 52, 54, 56, 65, 98, 238, 4321]
merge_Sort(seq)

def ins_sort_rec(seq,i):
    if i==0:  return
    ins_sort_rec(seq,i-1)
    j = i
    while j > 0 and seq[j - 1] > seq[j]:
        seq[j -1],seq[j] = seq[j], seq[j-1]
        j -=1
    return seq

seqq = [2,1,235,21,4,8,4,8,5,89,23,0,7,6]

a = ins_sort_rec(seqq,len(seqq)-1)
a 

def insertsort(seq):
    for i in range(1,len(seq)):
        j = i
        while seq[j] <seq[j-1] and j>0:
            seq[j],seq[j-1] = seq[j-1],seq[j]
            j -=1
    return seq

b = insertsort(seqq)
b

def changesort(seq):
    count = True
    while count:
        count = False
        for i in range(1,len(seq)):
            if seq[i]<seq[i-1]:
                seq[i],seq[i-1] = seq[i-1],seq[i]
                count =True
    return seq

ls = [2,1,235,21,4,8,4,8,5,89,23,0,7,6]
c = changesort(ls)
c

seqq = [2,1,235,21,4,8,4,8,5,89,23,0,7,6]


def selectsort(ls):
    for i in range(len(ls)-1):
        k = i
        for j in range(i,len(ls)):
            if ls[k] >ls[j]:
                k = j
        if k !=i:
            ls[i],ls[k]=ls[k],ls[i]
    return ls
selectsort(seqq)