Compilare: user.cpp: In function ‘int main()’: user.cpp:72:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ind.size(); i++) { ^ user.cpp:83:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); i++) { ^