fixmm.cpp

#include <string>
#include <regex>
#include <iostream>
#include <algorithm>

int main(int argc, char *argv[]) {
    std::string input = "5mm asdf 6mm asdf";
    std::string output = "";

    // If we get a good string from user, use that
    if (argc == 2) {
        input = argv[1];
    }

    // Matches words that have a digit, zero or more whitespaces, then the mm
    std::regex reg("[[:digit:]]+[[:space:]]*mm");
    std::smatch matches;


    // Match regex to string and record all the matches
    while (std::regex_search(input, matches, reg)) {
        // For each match

        // Pull everything before the match
        std::string pre = matches.prefix().str();
        // Make it caps
        std::transform(pre.begin(), pre.end(), pre.begin(), ::toupper);

        // Remove spaces from match
        std::string match = matches[0].str();
        match.erase(remove_if(match.begin(), match.end(), isspace), match.end());

        // Add to output variable
        output += pre + match;

        // Continue eating the string until all matches are found
        input = matches.suffix().str();
    }

    // Add anything after the last match to the output
    std::transform(input.begin(), input.end(), input.begin(), ::toupper);
    output += input;

    // Print out results
    std::cout << output << std::endl;
}