Consecutive Character Groups

#include <cctype>
#include <iostream>
#include <vector>

// Function to find consecutive character groups in a string
std::vector<std::pair<char, int>> solution(std::string s) {
    std::vector<std::pair<char, int>> groups; // Vector to store the groups of characters
    char current_group_char = '\0';           // Variable to hold the current character group
    int current_group_length = 0; // Variable to hold the length of the current character group

    for (char &c : s) {
        if (isalnum(c)) {                         // Check if the character is alphanumeric
            if (c == current_group_char) {        // If the character is part of the current group
                current_group_length += 1;        // Increment the length of the current group
            } else {                              // If the character starts a new group
                if (current_group_char != '\0') { // Push the previous group to groups if it exists
                    groups.push_back(std::make_pair(current_group_char, current_group_length));
                }
                current_group_char = c;   // Update the current character to the new group
                current_group_length = 1; // Reset the length for the new group
            }
        }
    }
    if (current_group_char != '\0') { // Add the last group if it exists
        groups.push_back(std::make_pair(current_group_char, current_group_length));
    }

    return groups; // Return the vector of groups
}