Compilare: user.cpp: In function ‘int main()’: user.cpp:7:7: warning: left operand of comma operator has no effect [-Wunused-value] in>>a,b; ~~^~~ user.cpp:7:12: warning: right operand of comma operator has no effect [-Wunused-value] in>>a,b; ^ user.cpp:9:8: warning: statement has no effect [-Wunused-value] out<<s; ~~~^~~ user.cpp:8:6: warning: ‘a’ is used uninitialized in this function [-Wuninitialized] s=a+b; ~^~~~ user.cpp:8:6: warning: ‘b’ is used uninitialized in this function [-Wuninitialized]