Compilare: user.cpp: In function ‘int unificare(int, int)’: user.cpp:19:15: warning: unused variable ‘k’ [-Wunused-variable] int r1,r2,k,C,x1,y1; ^ user.cpp:19:19: warning: variable ‘x1’ set but not used [-Wunused-but-set-variable] int r1,r2,k,C,x1,y1; ^~ user.cpp:19:22: warning: variable ‘y1’ set but not used [-Wunused-but-set-variable] int r1,r2,k,C,x1,y1; ^~ user.cpp: In function ‘int df(int, int)’: user.cpp:54:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v2[x].size(); i++) ~^~~~~~~~~~~~~ user.cpp:51:9: warning: unused variable ‘i’ [-Wunused-variable] int i; ^