Parse JSON file (C++ Boost)

UPDATE Since Boost 1.75 prefer Boost JSON, see below.

I think as usual you're just confused about how ptree stores JSON arrays?

Here's a quick demo:

Live On Coliru

#include <boost/property_tree/ptree.hpp> #include <boost/property_tree/json_parser.hpp> #include <iostream> #include <fstream> int main() { using namespace boost::property_tree; ptree pt; read_json(std::cin, pt); for (auto& challenge : pt.get_child("challenges")) for (auto& prop : challenge.second) std::cout << prop.first << ": " << prop.second.get_value<std::string>() << "\n"; } 

Prints:

question#1: answer value: 5 question: answer value: 5 question: answer value: 5 question: answer value: 5 question: answer value: 5 question: answer value: 5 question: answer value: 5 question: answer value: 5 question: answer value: 5 question: answer value: 5 

UPDATE: Better With Boost JSON

See it Live On Coliru

#include <boost/json.hpp> #include <boost/json/src.hpp> // for header only #include <iostream> int main() { std::string const input(std::istreambuf_iterator<char>(std::cin), {}); boost::json::error_code ec; auto doc = boost::json::parse(input, ec); for (auto& challenge : doc.at("challenges").as_array()) { std::cout << " --- " << challenge << "\n"; for (auto& [k,v] : challenge.as_object()) std::cout << k << ": " << v << "\n"; } } 

Prints

 --- {"question#1":"answer","value":5} question#1: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5 --- {"question":"answer","value":5} question: "answer" value: 5