Compilare: user.cpp: In function ‘void solve()’: user.cpp:30:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < q.size(); i++) ^ user.cpp:34:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); i++) ^ user.cpp:36:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < a[sol[i] ].size(); j++) ^ user.cpp: In function ‘void write()’: user.cpp:46:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); cout << sol[i++] << ' '); ^