Compilare: main.cpp: In function 'void C2()': main.cpp:41:9: warning: unused variable 'x1' [-Wunused-variable] int x1,x2,x3,x4; ^~ main.cpp:41:12: warning: unused variable 'x2' [-Wunused-variable] int x1,x2,x3,x4; ^~ main.cpp:41:15: warning: unused variable 'x3' [-Wunused-variable] int x1,x2,x3,x4; ^~ main.cpp:41:18: warning: unused variable 'x4' [-Wunused-variable] int x1,x2,x3,x4; ^~ main.cpp:42:12: warning: 'sol' may be used uninitialized in this function [-Wmaybe-uninitialized] char c,sol; ^~~ main.cpp:136:33: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized] fout<<x<<" "<<y<<"\n"<<sol<<"\n"; ^~~~ main.cpp:136:14: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized] fout<<x<<" "<<y<<"\n"<<sol<<"\n"; ^~~