Given an array arr[], the task is increment all the odd positioned elements by 1 and decrement all the even positioned elements by 1.
Examples:
Input: arr[] = {3, 6, 8}
Output: 4 5 9Input: arr[] = {9, 7, 3}
Output: 10 6 4
Approach: Traverse the array element by element and if the current element’s position is odd then increment it by 1 else decrement it by 1. Print the contents of the updated array in the end.
Below is the implementation of the above approach:
C++
// C++ implementation of the approach #include <bits/stdc++.h> using namespace std; // Utility function to print // the contents of an array void printArr( int arr[], int n) { for ( int i = 0; i < n; i++) cout << arr[i] << " " ; } // Function to increment all the odd // positioned elements by 1 and decrement // all the even positioned elements by 1 void updateArr( int arr[], int n) { for ( int i = 0; i < n; i++) // If current element is odd positioned if ((i + 1) % 2 == 1) arr[i]++; // If even positioned else arr[i]--; // Print the updated array printArr(arr, n); } // Driver code int main() { int arr[] = { 3, 6, 8 }; int n = sizeof (arr) / sizeof (arr[0]); updateArr(arr, n); return 0; } |
Java
// Java implementation of the approach class GfG { // Utility function to print // the contents of an array static void printArr( int arr[], int n) { for ( int i = 0 ; i < n; i++) System.out.print(arr[i] + " " ); } // Function to increment all the odd // positioned elements by 1 and decrement // all the even positioned elements by 1 static void updateArr( int arr[], int n) { for ( int i = 0 ; i < n; i++) // If current element is odd positioned if ((i + 1 ) % 2 == 1 ) arr[i]++; // If even positioned else arr[i]--; // Print the updated array printArr(arr, n); } // Driver code public static void main(String[] args) { int arr[] = { 3 , 6 , 8 }; int n = arr.length; updateArr(arr, n); } } // This code is contributed by Prerna Saini |
Python3
# Python3 implementation of the approach # Utility function to print # the contents of an array def printArr(arr, n): for i in range ( 0 , n): print (arr[i], end = " " ); # Function to increment all the odd # positioned elements by 1 and decrement # all the even positioned elements by 1 def updateArr(arr, n): for i in range ( 0 , n): # If current element is odd positioned if ((i + 1 ) % 2 = = 1 ): arr[i] + = 1 ; # If even positioned else : arr[i] - = 1 ; # Print the updated array printArr(arr, n); # Driver code if __name__ = = '__main__' : arr = [ 3 , 6 , 8 ]; n = len (arr); updateArr(arr, n); # This code contributed by PrinciRaj1992 |
C#
// C# implementation of the approach class GfG { // Utility function to print // the contents of an array static void printArr( int []arr, int n) { for ( int i = 0; i < n; i++) System.Console.Write(arr[i] + " " ); } // Function to increment all the odd // positioned elements by 1 and decrement // all the even positioned elements by 1 static void updateArr( int []arr, int n) { for ( int i = 0; i < n; i++) // If current element is odd positioned if ((i + 1) % 2 == 1) arr[i]++; // If even positioned else arr[i]--; // Print the updated array printArr(arr, n); } // Driver code static void Main() { int []arr = { 3, 6, 8 }; int n = arr.Length; updateArr(arr, n); } } // This code is contributed by mits |
PHP
<?php // PHP implementation of the approach // Utility function to print // the contents of an array function printArr( $arr , $n ) { for ( $i = 0; $i < $n ; $i ++) echo $arr [ $i ] . " " ; } // Function to increment all the odd // positioned elements by 1 and decrement // all the even positioned elements by 1 function updateArr( $arr , $n ) { for ( $i = 0; $i < $n ; $i ++) // If current element is odd positioned if (( $i + 1) % 2 == 1) $arr [ $i ]++; // If even positioned else $arr [ $i ]--; // Print the updated array printArr( $arr , $n ); } // Driver code $arr = array ( 3, 6, 8 ); $n = count ( $arr ); updateArr( $arr , $n ); // This code is contributed by mits ?> |
Javascript
<script> // javascript implementation of the approach // Utility function to print // the contents of an array function printArr(arr, n) { var i; for (i = 0; i < n; i++) document.write(arr[i] + " " ); } // Function to increment all the odd // positioned elements by 1 and decrement // all the even positioned elements by 1 function updateArr(arr, n) { var i; for (i = 0; i < n; i++) // If current element is odd positioned if ((i + 1) % 2 == 1) arr[i]++; // If even positioned else arr[i]--; // Print the updated array printArr(arr, n); } // Driver code var arr = [3, 6, 8]; var n = arr.length; updateArr(arr, n); </script> |
4 5 9
Time Complexity: O(n)
Auxiliary Space: O(1)
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