Amazing-Python-Scripts

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# -*- coding: utf-8 -*-
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"""
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Author: Himanshu Agarwal
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Github: himanshu-03 (http://github.com/himanshu-03)
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LinkedIn: agarwal-himanshu (https://linkedin.com/in/agarwal-himanshu)
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# Merge Sort
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"""
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def merger(a, start, mid, end):
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    temp = []
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    for i in range(len(a)):
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        temp.append(0)
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    i = start
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    j = mid + 1
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    ti = start
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    while i <= mid and j <= end:
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        if a[i] < a[j]:
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            temp[ti] = a[i]
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            ti += 1
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            i += 1
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        else:
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            temp[ti] = a[j]
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            ti += 1
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            j += 1
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    while i <= mid:
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        temp[ti] = a[i]
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        ti += 1
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        i += 1
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    while j <= end:
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        temp[ti] = a[j]
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        ti += 1
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        j += 1
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    for i in range(start, end+1):
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        a[i] = temp[i]
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def mergesort(a, start, end):
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    if start < end:
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        mid = (start+end)//2
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        mergesort(a, start, mid)
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        mergesort(a, mid+1, end)
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        merger(a, start, mid, end)
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a = []
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size = int(input('Enter size of array: '))
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print('')
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for i in range(size):
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    data = int(input('Enter element: '))
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    a.append(data)
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print('')
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print('Elements are: ', a)
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mergesort(a, 0, len(a)-1)
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print('After sorting elements are: ', a)
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