cin, cout and cerr in C++

cin, cout and cerr in C++ — a practical guide to C++ cin cout cerr with clear examples you can reuse in real projects.

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Short description

cerr is typically unbuffered — good for diagnostics.

cin/cout/cerr

int age;
std::cout << "Age: ";
if (std::cin >> age) {
    std::cout << "You are " << age << 'n';
} else {
    std::cerr << "Invalid inputn";
}