Compilare: main.cpp: In function 'long long int toNumber(std::__cxx11::string)': main.cpp:11:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int it = 0; it < S.size(); ++it) { ~~~^~~~~~~~~~ main.cpp: In function 'void solve()': main.cpp:36:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int it = 0; it < s.size(); ++it) { ~~~^~~~~~~~~~ main.cpp:37:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (s[it] > '0' && it + 1 < s.size() && s[it] < s[it + 1]) { ~~~~~~~^~~~~~~~~~ main.cpp:40:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < s.size(); ++j){ ~~^~~~~~~~~~ main.cpp:43:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (s.size() - 1 - j != it) ~~~~~~~~~~~~~~~~~^~~~~