What's the difference between cout << "\n" and cout << '\n'?

23:41 10 Jan 2026

cout << "Optimal train swapping takes " << cnt << " swaps." << '\n';

Give the wrong answer

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Then I try the code that end with "\n", it correct.

cout << "Optimal train swapping takes " << cnt << " swaps." << "\n";

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Is there any reason that make the different?

c++ c++11