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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# Binary Search (Recursive)
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"""
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# Recursive Method
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def binarysearch(a, start, end, key):
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    if start == end:
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        if a[start] == key:
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            return start
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        else:
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            return -1
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    else:
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        mid = (start+end)//2
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        if a[mid] == key:
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            return mid
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        elif a[mid] > key:
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            return binarysearch(a, start, mid-1, key)
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        else:
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            return binarysearch(a, mid+1, end, key)
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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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key = int(input('Enter key to search: '))
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res = binarysearch(a, 0, len(a)-1, key)
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if res == -1:
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    print(key, 'not found..!!')
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else:
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    print(key, 'found at', res+1, 'location')
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