C++ Exercises: Create a new array taking the first and last elements of a given array of integers and length 1 or more

Last update on December 20 2024 12:28:38 (UTC/GMT +8 hours)

First and Last Elements of Array

Write a C++ program to create an array taking the first and last elements of a given array of integers and length 1 or more.

Sample Solution:

C++ Code :

#include <iostream> // Including the input/output stream library
using namespace std; // Using the standard namespace

// Function that creates and returns an array containing the first and last elements of the input array
int *test(int nums[], int arr_length) {
   // Static array storing the first and last elements of the nums array
   static int r_array[] = {nums[0], nums[arr_length - 1] }; 
   return r_array; // Returning the new array
}

// Main function
int main () {
   int *p; // Pointer to an integer

   int nums[] = { 10, 20, -30, -40, 30 }; // Define an array nums
   int arr_length = sizeof(nums) / sizeof(nums[0]); // Calculate the length of nums

   cout << "Original array: " << endl;   
   for ( int i = 0; i < arr_length; i++ ) {    
      cout << nums[i] << " "; // Output the original array
   }

   p = test(nums, arr_length); // Store the result of test function in pointer p
   arr_length = sizeof(p) / sizeof(p[0]); // Calculate the length of p (which won't work correctly)
   cout << "\nNew array: " << endl;
   for ( int i = 0; i < arr_length; i++ ) {
      cout << *(p + i) << " "; // Output the new array elements (this size calculation won't work correctly)
   }

   return 0; // Return statement indicating successful termination of the program
}

Sample Output:

Original array:
10 20 -30 -40 30
New array:
10 30

Visual Presentation:

Flowchart:

C++ Code Editor:

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