Compilare: user.cpp: In function ‘int read()’: user.cpp:34:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int solve()’: user.cpp:51:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int write()’: user.cpp:58:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<apm.size();++i) ^ user.cpp:60:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^