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| 1 | +# Linear Search algorithm |
| 2 | +# Linear search is defined as the searching algorithm |
| 3 | +# where the list or data set is traversed from one end to find the desired value. |
| 4 | +# Time Complexity: The worst case time complexity of linear search is o(n), where n is the size of the array. |
| 5 | +# Space Complexity: Linear search requires a constant amount of memory to run. |
| 6 | +# Efficiency: Linear search is effeicient for small datasets but becomes inefficient for larger datasets. |
| 7 | +# In practice, linear search is often used as a subroutine in more complex algorithms. |
| 8 | +# Implementation: Linear search can be easily implemented using a loop, |
| 9 | +# with each iteration comparing the target value to the current element of the array. |
| 10 | +# |
| 11 | +# def search(arr, N, x): |
| 12 | +# for i in range(0, N): |
| 13 | +# if arr[i] == x: |
| 14 | +# return i |
| 15 | +# return -1 |
| 16 | + |
| 17 | +# arr =[int(i) for i in input('Enter the array with comma').split(',')] |
| 18 | +# x = int(input('enter the number:')) |
| 19 | +# N = len(arr) |
| 20 | +# result = search(arr, N, x) |
| 21 | +# if(result == -1): |
| 22 | +# print("Element is not present in array") |
| 23 | +# else: |
| 24 | +# print("Element is present at index", result) |
| 25 | + |
| 26 | +# Phonebook Search: Linear search can be used to search through a phonebook to find a person’s name, given their phone number. |
| 27 | +# Spell Checkers: The algorithm compares each word in the document to a dictionary of correctly spelled words until a match is found. |
| 28 | +# Finding Minimum and Maximum Values: Linear search can be used to find the minimum and maximum values in an array or list. |
| 29 | +# Searching through unsorted data: Linear search is useful for searching through unsorted data. |
| 30 | + |
| 31 | + |
| 32 | +#sentinellinear search |
| 33 | +# def sentinelLinearSearch(array, key): |
| 34 | +# last = array[len(array) - 1] |
| 35 | +# array[len(array) - 1] = key |
| 36 | +# i = 0 |
| 37 | +# while array[i] != key: |
| 38 | +# i += 1 |
| 39 | +# array[len(array) - 1] = last |
| 40 | +# if i < len(array) - 1 or last == key: |
| 41 | +# return i |
| 42 | +# else: |
| 43 | +# return -1 |
| 44 | + |
| 45 | +# array = [1, 2, 3, 4, 5, 6, 7, 8, 9] |
| 46 | +# key = 5 |
| 47 | +# index = sentinelLinearSearch(array, key) |
| 48 | +# if index == -1: |
| 49 | +# print(f"{key} is not found in the array: {array}") |
| 50 | +# else: |
| 51 | +# print(f"{key} is found at index {index} in the array: {array}") |
| 52 | + |
| 53 | + |
| 54 | + |
| 55 | +# Binary search |
| 56 | + |
| 57 | +# Divide the search space into two halves by finding the middle index “mid”. |
| 58 | +# Compare the middle element of the search space with the key. |
| 59 | +# If the key is found at middle element, the process is terminated. |
| 60 | +# If the key is not found at middle element, choose which half will be used as the next search space. |
| 61 | +# If the key is smaller than the middle element, then the left side is used for next search. |
| 62 | +# If the key is larger than the middle element, then the right side is used for next search. |
| 63 | +# This process is continued until the key is found or the total search space is exhausted. |
| 64 | + |
| 65 | +# Python3 code to implement iterative Binary search |
| 66 | +# It returns location of x in given array arr |
| 67 | + |
| 68 | + |
| 69 | +# def binarySearch(arr, l, r, x): |
| 70 | +# while l<=r: |
| 71 | +# mid=l+(r-1)//2 |
| 72 | +# if arr[mid]==x: |
| 73 | +# return mid |
| 74 | +# elif arr[mid]<x: |
| 75 | +# l=mid+1 |
| 76 | +# else: |
| 77 | +# r=mid-1 |
| 78 | +# return -1 |
| 79 | +# # If we reach here, then the element |
| 80 | +# # was not present |
| 81 | +# arr = [int(i) for i in input('enter array: ').split(",")] |
| 82 | +# x = 10 |
| 83 | +# result = binarySearch(arr, 0, len(arr)-1, x) |
| 84 | +# if result != -1: |
| 85 | +# print("Element is present at index", result) |
| 86 | +# else: |
| 87 | +# print("Element is not present in array") |
| 88 | + |
| 89 | + |
| 90 | +# Implementation of Recursive Binary Search Algorithm: |
| 91 | + |
| 92 | +# def binary(arr,l,r,x): |
| 93 | +# if r>=l: |
| 94 | +# mid=l+(r-1)//2 |
| 95 | +# if arr[mid]==x: |
| 96 | +# return mid |
| 97 | +# elif arr[mid]>x: |
| 98 | +# return binary(arr,l,mid-1,x) |
| 99 | +# else: |
| 100 | +# return binary(arr,mid+1,r,x) |
| 101 | +# return -1 |
| 102 | +# arr = [int(i) for i in input('enter array: ').split(",")] |
| 103 | +# x = 10 |
| 104 | +# result = binary(arr, 0, len(arr)-1, x) |
| 105 | +# if result != -1: |
| 106 | +# print("Element is present at index", result) |
| 107 | +# else: |
| 108 | +# print("Element is not present in array") |
| 109 | + |
| 110 | +# Time Complexity: |
| 111 | +# Best Case: O(1) |
| 112 | +# Average Case: O(log N) |
| 113 | +# Worst Case: O(log N) |
| 114 | +# Auxiliary Space: O(1), If the recursive call stack is considered then the auxiliary space will be O(logN). |
| 115 | + |
| 116 | +# class Node: |
| 117 | +# def __init__(self,data): |
| 118 | +# self.data=data |
| 119 | +# self.next=None |
| 120 | + |
| 121 | +# class Sll: |
| 122 | +# def __init__(self): |
| 123 | +# self.head=None |
| 124 | + |
| 125 | +# def tranversal(self): |
| 126 | +# if self.head is None: |
| 127 | +# print("linked list is empty") |
| 128 | +# else: |
| 129 | +# a=self.head |
| 130 | +# while a is not None: |
| 131 | +# print(a.data,end=" ") |
| 132 | +# a=a.next |
| 133 | + |
| 134 | +# n1=Node(5) |
| 135 | +# sll=Sll() |
| 136 | +# sll.head=n1 |
| 137 | +# n2=Node(10) |
| 138 | +# n1.next=n2 |
| 139 | +# n3=Node(15) |
| 140 | +# n2.next=n3 |
| 141 | +# n4=Node(20) |
| 142 | +# n3.next=n4 |
| 143 | +# sll.tranversal() |
| 144 | + |
| 145 | +# def search(arr,v): |
| 146 | +# l=len(arr) |
| 147 | +# for i in range(l): |
| 148 | +# if arr[i]==v: |
| 149 | +# return i |
| 150 | +# else: |
| 151 | +# return -1 |
| 152 | + |
| 153 | +# def search(arr,l,r,v): |
| 154 | +# while l<=r: |
| 155 | +# mid=l+(r-1)//2 |
| 156 | +# if arr[mid]==v: |
| 157 | +# return mid |
| 158 | +# elif arr[mid]<r: |
| 159 | +# l=mid+1 |
| 160 | +# else: |
| 161 | +# r=mid-1 |
| 162 | +# return -1 |
| 163 | + |
| 164 | + |
| 165 | +# def search(arr,l,r,v): |
| 166 | +# if l<=r: |
| 167 | +# mid=l+(r-1)//2 |
| 168 | +# if arr[mid]==v: |
| 169 | +# return mid |
| 170 | +# elif arr[mid]>r: |
| 171 | +# return search(arr,l,mid-1,v) |
| 172 | +# else: |
| 173 | +# return search(arr,mid+1,r,v) |
| 174 | +# return -1 |
| 175 | + |
| 176 | + |
| 177 | + |
| 178 | +# arr=[int(x)for x in input('array').split(",")] |
| 179 | +# v=int(input()) |
| 180 | +# result=search(arr,0,len(arr),v) |
| 181 | +# print(result) |
| 182 | + |
| 183 | +# def partition(data,l,r): |
| 184 | +# pivot=data[r] |
| 185 | +# i=l-1#0 |
| 186 | +# for j in range(l,r): |
| 187 | +# if data[j]<=pivot: |
| 188 | +# i=i+1 |
| 189 | +# (data[i],data[j])=(data[j],data[i]) |
| 190 | +# (data[i+1],data[r])=(data[r],data[i+1]) |
| 191 | +# return i+1 |
| 192 | + |
| 193 | + |
| 194 | + |
| 195 | +# def quickSort(data,l,r): |
| 196 | +# if l<r: |
| 197 | +# pi=partition(data,l,r) |
| 198 | +# quickSort(data,l,pi-1) |
| 199 | +# quickSort(data,pi+1,r) |
| 200 | + |
| 201 | + |
| 202 | + |
| 203 | +# data=[1,7,4,1,10,9,-2] |
| 204 | +# print("Unsorted Array") |
| 205 | +# print(data) |
| 206 | +# r=len(data)-1 |
| 207 | +# print(r) |
| 208 | +# quickSort(data,0,r) |
| 209 | +# print('Sorted Array in Ascending Order:') |
| 210 | +# print(data) |
| 211 | + |
| 212 | + |
| 213 | +# Approach 2: Quicksort using list comprehension |
| 214 | + |
| 215 | +# def quicksort(arr): |
| 216 | +# if len(arr) <= 1: |
| 217 | +# return arr |
| 218 | +# else: |
| 219 | +# pivot = arr[0] |
| 220 | +# left = [x for x in arr[1:] if x < pivot] |
| 221 | +# right = [x for x in arr[1:] if x >= pivot] |
| 222 | +# return quicksort(left) + [pivot] + quicksort(right) |
| 223 | + |
| 224 | +# # Example usage |
| 225 | +# arr = [1, 7, 4, 1, 10, 9, -2] |
| 226 | +# sorted_arr = quicksort(arr) |
| 227 | +# print("Sorted Array in Ascending Order:") |
| 228 | +# print(sorted_arr) |
| 229 | + |
| 230 | + |
| 231 | +def insertionSort(arr): |
| 232 | + n = len(arr) # Get the length of the array |
| 233 | + |
| 234 | + if n <= 1: |
| 235 | + return # If the array has 0 or 1 element, it is already sorted, so return |
| 236 | + |
| 237 | + for i in range(1, n): # Iterate over the array starting from the second element |
| 238 | + key = arr[i] # Store the current element as the key to be inserted in the right position |
| 239 | + j = i-1 |
| 240 | + while j >= 0 and key < arr[j]: # Move elements greater than key one position ahead |
| 241 | + arr[j+1] = arr[j] # Shift elements to the right |
| 242 | + j -= 1 |
| 243 | + arr[j+1] = key # Insert the key in the correct position |
| 244 | + |
| 245 | +# Sorting the array [12, 11, 13, 5, 6] using insertionSort |
| 246 | +arr = [12, 11, 13, 5, 6] |
| 247 | +insertionSort(arr) |
| 248 | +print(arr) |
| 249 | + |
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