Compilare: user.cpp: In function ‘int main()’: user.cpp:41:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<q.size();i++) ^ user.cpp:45:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<a[x].size();j++) ^ user.cpp:72:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<a[x].size();i++) ^ user.cpp:78:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (x!=y) for (j=0;j<a[y].size();j++) ^ user.cpp:92:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<a[x].size();i++) ^ user.cpp:99:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<a[y].size();j++) ^