Compilare: user.cpp: In function ‘int main()’: user.cpp:14:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (D.size()<=n) ^ user.cpp:17:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k=0; k<D.size(); k++) ^ user.cpp:19:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (D[k]!=' ' && k+1!=D.size()) ^ user.cpp:23:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (k+1==D.size()) ^ user.cpp:25:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (A.size()+len<=n) ^ user.cpp:39:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<sol.size(); i++) ^