Modernes C++ programmieren

//#(compile) c++; compiler:g132; options:-O3 -std=c++23; libs:-
// https://godbolt.org/z/d6PscKx4M 
#include <map>
#include <string>
#include <algorithm> // any_of
#include <iostream>  // cerr
std::map<int, std::string> m;
int main() {
   if(auto it = m.find(10); it != m.end()) { return it->second.size(); }
   if(char buf[10]={0}; std::fgets(buf, 10, stdin)) { m[0] += buf; }
   std::string s;
   if(auto keywords = {"if", "for", "while"};
       std::any_of(keywords.begin(), keywords.end(),
       [&s](const char* kw) { return s == kw; })) {
           std::cerr << "Fehler\n";
   }
}