C++ Exercises: Array from an existing array using string length

C++ Basic Algorithm: Exercise-121 with Solution

Write a C++ program to create an array from a given array of strings using all the strings whose lengths are matched with the given string length.

Test Data:
({a,aaa,b,bb,bbb,c,cc,ccc},1) -> {a,b,c}
({a,aaa,b,bb,bbb,c,cc,ccc},2) -> {bb, cc}

Sample Solution:

C++ Code :

#include <iostream>  // Including input-output stream header file

#include<string.h>   // Including string manipulation header file

using namespace std;  // Using standard namespace

string *new_array;  // Declaring a pointer for the new string array
int ctr = 0;  // Counter variable to track strings of a certain length

// Function to create a new string array containing strings of a given length
string *test(string *text, int arr_length, int n) {
    int i = 0, j = 0;  // Loop control variables

    // Counting the number of strings with length 'n' in the input array 'text'
    for (i = 0; i < arr_length; i++) {
        if (text[i].size() == n)
            ctr++;  // Incrementing counter for strings of length 'n'
    }

    new_array = new string[ctr];  // Allocating memory for the new string array

    // Copying strings of length 'n' from the input array 'text' to the new array 'new_array'
    for (i = 0; i < arr_length; i++) {
        if (text[i].size() == n) {
            new_array[j] = text[i];  // Copying the string of length 'n' to 'new_array'
            j++;  // Incrementing index of the new array
        }
    }

    return new_array;  // Returning the pointer to the new string array
}

// Main function
int main() {
    string text[] = {"a", "aaa", "b", "bb", "bbb", "c", "cc", "ccc"};  // Original array of strings

    string *result_array;  // Pointer to store the returned new string array

    int arr_length = sizeof(text) / sizeof(text[0]);  // Calculating the length of the original array
    cout << "Original array elements: " << endl;

    // Displaying the original array elements
    for (int i = 0; i < arr_length; i++) {
        std::cout << text[i] << ' ';
    }

    int n = 1;  // String length to filter the new array
    result_array = test(text, arr_length, n);  // Calling 'test' function to create a new array
    cout << "\n\nNew array with given string length = " << n << endl;

    // Displaying the new array containing strings of length 'n'
    for (int i = 0; i < ctr; i++) {
        std::cout << result_array[i] << ' ';
    }

    n = 2;  // Changing the string length to filter the new array
    result_array = test(text, arr_length, n);  // Creating a new array with updated string length
    cout << "\n\nNew array with given string length = " << n << endl;

    // Displaying the new array containing strings of length 'n'
    for (int i = 0; i < ctr; i++) {
        std::cout << result_array[i] << ' ';
    }

    delete[] new_array;  // Deleting the allocated memory for the new array

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

Sample Output:

Original array elements: 
a aaa b bb bbb c cc ccc 

New array with given string length = 1
a b c 

New array with given string length = 2
bb cc    

Flowchart:

C++ Code Editor:

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