#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/phoenix.hpp>
#include <string>
 
int main() {
    std::string expression = "2<2";
    int result = 0;
 
    using namespace boost::spirit::qi;
    using namespace boost::phoenix;
    bool success = parse(expression.begin(), expression.end(), int_[ref(result) = _1]);
 
    if (success) {
        std::cout << "Result: " << result << std::endl;
    } else {
        std::cout << "Failed to parse expression" << std::endl;
    }
 
    return 0;
}
 

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