Compilare: user.cpp: In function ‘void dfs(int, int, int, int)’: user.cpp:41:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[vf].size();++i) ^ user.cpp: In function ‘int solve(int, int)’: user.cpp:88:24: warning: variable ‘z1’ set but not used [-Wunused-but-set-variable] int X1,X2,logs,LCA,z1,z2,z3,dif,mina,minb; ^ user.cpp:88:27: warning: variable ‘z2’ set but not used [-Wunused-but-set-variable] int X1,X2,logs,LCA,z1,z2,z3,dif,mina,minb; ^ user.cpp:88:30: warning: variable ‘z3’ set but not used [-Wunused-but-set-variable] int X1,X2,logs,LCA,z1,z2,z3,dif,mina,minb; ^ user.cpp:88:33: warning: unused variable ‘dif’ [-Wunused-variable] int X1,X2,logs,LCA,z1,z2,z3,dif,mina,minb; ^ user.cpp:88:37: warning: unused variable ‘mina’ [-Wunused-variable] int X1,X2,logs,LCA,z1,z2,z3,dif,mina,minb; ^ user.cpp:88:42: warning: unused variable ‘minb’ [-Wunused-variable] int X1,X2,logs,LCA,z1,z2,z3,dif,mina,minb; ^