Compilare: main.cpp: In function 'int main()': main.cpp:107:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (ask.size() != len) { ~~~~~~~~~~~^~~~~~ main.cpp: In function 'std::__cxx11::string getK(long long int)': main.cpp:35:27: warning: 'cur' may be used uninitialized in this function [-Wmaybe-uninitialized] long long val = cur * aux[i] / (len - pos); ~~~~^~~~~~~~