Compilare: user.cpp: In function ‘void strmatch()’: user.cpp:12:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(poz<b.size()) ^ user.cpp:15:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(fid<a.size() && poz<b.size() && a[fid]==b[poz]) ^ user.cpp:15:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(fid<a.size() && poz<b.size() && a[fid]==b[poz]) ^ user.cpp:21:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(fid==a.size()) ^ user.cpp: In function ‘int main()’: user.cpp:53:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<a.size();i++) ^