Compilare: user.cpp: In function ‘int main()’: user.cpp:22:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<a.size();i++) ^ user.cpp:28:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<b.size()-1;i++) ^ user.cpp:48:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=b.size();i++) p[i]=0; ^ user.cpp:51:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<a.size();i++) ^ user.cpp:58:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<b.size()-1;i++) ^