Compilare: main.cpp: In function 'int main()': main.cpp:17:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < s2.size(); ++i) ~~^~~~~~~~~~~ main.cpp:80:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for (int i = 1; i <= top; ++i) ^~~ main.cpp:82:9: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' fout << ans; ^~~~