C++ String Exercises: Find the numbers in a string and calculate the sum

Last update on December 20 2024 12:32:14 (UTC/GMT +8 hours)

Write a C++ program to find the numbers in a given string and calculate the sum of all numbers.

Visual Presentation:

Sample Solution:

C++ Code :

#include <iostream> // Including input/output stream library
#include <string> // Including string library for string operations

using namespace std; // Using the standard namespace

// Function to find numbers in a string and calculate their sum
int find_nums_and_sum(string str) {

    int sum_num = 0; // Initializing the variable to store the sum of numbers found
    string temp_str; // Creating a temporary string to store consecutive digits

    // Loop through each character in the string
    for (int x = 0; x < str.length(); x++)
    {
        // Check if the character is a digit
        if (isdigit(str[x]))
        {
            temp_str.push_back(str[x]); // Add the digit to the temporary string

            // Loop to find consecutive digits in the string
            for (int y = x + 1; y < str.length(); y++)
            {
                // Check if the index exceeds the string length
                if (y >= str.length())
                {
                    break;
                }
                // Check if the next character is a digit
                else if (isdigit(str[y]))
                {
                    temp_str.push_back(str[y]); // Add the digit to the temporary string
                    x = y; // Update the current index to the next digit
                }
                else
                {
                    break;
                }
            }

            sum_num += stoi(temp_str); // Convert the temporary string to an integer and add to the sum
            temp_str.clear(); // Clear the temporary string for the next sequence of digits
        }
    }

    return sum_num; // Return the sum of numbers found in the string
}

// Main function
int main() {

    // Output the original strings and their corresponding sum of numbers found
    cout << "Original string: 91, ABC Street.-> Sum of the numbers: "<< find_nums_and_sum("91, ABC Street.") << endl;
    cout << "Original string: w3resource from 2008->  Sum of the numbers: "<< find_nums_and_sum("w3resource from 2008") << endl;
    cout << "Original string: C++ Versiuon 14aa11bb23->  Sum of the numbers: "<< find_nums_and_sum("C++ Versiuon 14aa11bb23") << endl; 
    return 0; // Return 0 to indicate successful completion
}

Sample Output:

Original string: 91, ABC Street.-> Sum of the numbers: 91
Original string: w3resource from 2008->  Sum of the numbers: 2011
Original string: C++ Versiuon 14aa11bb23->  Sum of the numbers: 48

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