Alphabet upper case with std::regex

#include <iostream>
#include <string>
#include <regex>
#include <vector>

using namespace std;

struct Replacement {
    string Before;
    string After;
    Replacement(string Before, string After)
        : Before(Before), After(After) {}
};

int main()
{
    vector<Replacement> rep = {
        {"a", "A"},{"b", "B"},{"c", "C"},{"d", "D"},
        {"e", "E"},{"f", "F"},{"g", "G"},{"h", "H"},
        {"i", "I"},{"j", "J"},{"k", "K"},{"l", "L"},
        {"m", "M"},{"n", "N"},{"o", "O"},{"p", "P"},
        {"q", "Q"},{"r", "R"},{"s", "S"},{"t", "T"},
        {"u", "U"},{"v", "V"},{"w", "W"},{"x", "X"},
        {"y", "Y"},{"z", "Z"}
    };

    string str = "hello my name is...";

    for(const Replacement repl: rep)
    {
        regex rx(repl.Before);
        str = regex_replace(str, rx, repl.After);
    }

    cout << str << endl;
}