1: def mergesort(seq):
2: if len(seq)<=1:
3: return seq
4: mid=len(seq)/2
5: left=mergesort(seq[:mid])
6: right=mergesort(seq[mid:])
7: return merge(left,right)
8:
9: def merge(left,right):
10: result=[]
11: i,j=0,0
12: while i<len(left) and j<len(right):
13: if left[i]<=right[j]:
14: result.append(left[i])
15: i+=1
16: else:
17: result.append(right[j])
18: j+=1
19: result+=left[i:]
20: result+=right[j:]
21: return result
22:
23: if __name__==‘__main__‘:
24: seq=[4,5,7,9,7,5,1,0,7,-2,3,-99,6]
25: print(mergesort(seq))