C++ Dynamic Memory Allocation: Array of integers and strings initialization

Last update on April 12 2025 12:57:53 (UTC/GMT +8 hours)

2. Dynamically Allocate an Array of Integers and Strings

Write a C++ program to dynamically allocate an array of integers and strings and initialize its elements.

Sample Solution:

C Code:

#include <iostream>  // Including the Input/Output Stream Library
#include <string>    // Including the String Library

int main() {
  // Dynamically allocate an array of integers
  int size = 7; // Size of the array
  int * dynamicIntArray = new int[size]; // Allocating memory for an integer array of 'size' elements

  // Initialize the elements of the integer array
  for (int i = 0; i < size; i++) {
    dynamicIntArray[i] = i + 1; // Setting values in the dynamically allocated integer array
  }

  // Dynamically allocate an array of strings
  std::string * dynamicStringArray = new std::string[size]; // Allocating memory for a string array of 'size' elements

  // Initialize the elements of the string array
  for (int i = 0; i < size; i++) {
    dynamicStringArray[i] = "Element-" + std::to_string(i + 1); // Setting values in the dynamically allocated string array
  }

  // Display the elements of the dynamically allocated integer array
  std::cout << "Dynamically allocated integer array:" << std::endl;
  for (int i = 0; i < size; i++) {
    std::cout << dynamicIntArray[i] << " "; // Outputting each element of the dynamically allocated integer array
  }
  std::cout << std::endl;

  // Display the elements of the dynamically allocated string array
  std::cout << "\nDynamically allocated string array:" << std::endl;
  for (int i = 0; i < size; i++) {
    std::cout << dynamicStringArray[i] << std::endl; // Outputting each element of the dynamically allocated string array
  }

  // Deallocate the memory allocated for both arrays
  delete[] dynamicIntArray; // Deallocating memory for the dynamically allocated integer array
  delete[] dynamicStringArray; // Deallocating memory for the dynamically allocated string array

  return 0; // Returning 0 to indicate successful execution of the program
}

Sample Output:

Dynamically allocated integer array:
1 2 3 4 5 6 7

Dynamically allocated string array:
Element-1
Element-2
Element-3
Element-4
Element-5
Element-6
Element-7

Explanation:

In the above exercise -

• Use the new operator to dynamically allocate memory for an array of integers and strings. The array size is determined by the variable size.
• Initialize the integer array with values from 1 to size using a for loop. Similarly, initialize the string array elements with strings like "Element 1", "Element 2", etc.
• Next display the elements of both arrays using std::cout. The integer array elements are displayed on a single line separated by spaces, while the string array elements are displayed one per line.
• Finally, deallocate dynamically allocated memory using the delete[] operator for both arrays.

Flowchart:

For more Practice: Solve these Related Problems:

• Write a C++ program to dynamically allocate an array of 10 integers and initialize each element with its index value multiplied by 2, then print the array.
• Write a C++ program to dynamically allocate an array of strings of size n (input by the user) and populate each element with a default message, then display the array.
• Write a C++ program to create two dynamic arrays—one for integers and one for strings—and initialize them with random numbers and sample text respectively, then print both arrays side by side.
• Write a C++ program to dynamically allocate an array of integers and another array of strings, then allow the user to input values for both and display them in a formatted table.

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