C++ Vector Exercises: Find strings that contain a number(s) from a vector

Last update on December 20 2024 12:32:40 (UTC/GMT +8 hours)

Write a C++ program that takes a vector of strings and returns only those strings that contain a number(s). Return an empty vector if none.

Sample Data:
({"red", "green23", "1black", "white"}) -> ("green23", "1black")
({"red", "green", "black", "white"}) -> ( )

Sample Solution-1:

C++ Code:

#include <algorithm>  // Including the Algorithm Library for certain functions like find_if
#include <iostream>   // Including the Input/Output Stream Library
#include <vector>     // Including the Vector Library for using vectors

using namespace std;  // Using the Standard Namespace

// Function to find strings in the vector that contain at least one digit
std::vector<std::string> test(std::vector<std::string> colors) {
  std::vector<std::string> result; // Creating a new vector to store strings containing digits

  // Loop through each string in the input vector 'colors'
  for(auto& text : colors){
    auto it = std::find_if(text.begin(), text.end(), [](char c){return std::isdigit(c);}); // Using find_if to search for a digit in the current string

    if(it != text.end()){ // If a digit is found in the string
      result.push_back(text); // Add the string to the 'result' vector
    }
  }
  return result; // Return the vector containing strings with digits
}

// Main function
int main(){
	vector<string> colors = {"red", "green23", "1black", "white"}; // Initializing a vector of strings

    cout << "Original Vector elements:\n";
	for (string c : colors)
        cout << c << " "; // Printing the original elements of the vector

    vector<string> result = test(colors); // Calling the test function to find strings containing digits
    cout << "\n\nFind strings that contain a number(s) from the said vector:\n";   
    for (string c : result)
        cout << c << " "; // Printing the strings containing digits from the 'result' vector
}

Sample Output:

Original Vector elements:
red green23 1black white 

Find strings that contain a number(s) from the said vector:
green23 1black

Flowchart:

Sample Solution-2:

C++ Code:

#include <algorithm>  // Including the Algorithm Library for certain functions like isdigit
#include <iostream>   // Including the Input/Output Stream Library
#include <vector>     // Including the Vector Library for using vectors

using namespace std;  // Using the Standard Namespace

// Function to find strings in the vector that contain at least one digit
std::vector<std::string> test(std::vector<std::string> colors) {
    vector<string> result; // Creating a new vector to store strings containing digits

    // Loop through each string in the input vector 'colors'
    for(string i : colors) {
        // Loop through each character in the string
        for(char el : i) {
            if(isdigit(el)) { // If a digit is found in the string
                result.push_back(i); // Add the string to the 'result' vector
                break; // Break the loop as soon as a digit is found in the string
            }
        }
    }
    return result; // Return the vector containing strings with digits
}

// Main function
int main() {
    vector<string> colors = {"red", "green23", "1black", "white"}; // Initializing a vector of strings

    cout << "Original Vector elements:\n";
    for (string c : colors)
        cout << c << " "; // Printing the original elements of the vector

    vector<string> result = test(colors); // Calling the test function to find strings containing digits
    cout << "\n\nFind strings that contain a number(s) from the said vector:\n";   
    for (string c : result)
        cout << c << " "; // Printing the strings containing digits from the 'result' vector
}

Sample Output:

Original Vector elements:

red green23 1black white
 

Find strings that contain a number(s) from the said vector:

green23 1black

Flowchart:

C++ Code Editor:

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