#include <iostream>
#include <string>
#include <regex>
 
int main()
{
    std::string input = "Content-Type: text/plain";
    std::regex contentTypeRegex("Content-Type: (.+)");
 
    std::smatch match;
 
    if (std::regex_match(input, match, contentTypeRegex)) {
         std::ssub_match contentTypeMatch = match[1];
         std::string contentType = contentTypeMatch.str();
         std::cout << contentType;
    }
    //else not found
    return 0;
}

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