Compilare: user.cpp: In function ‘int main()’: user.cpp:108:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^ user.cpp:111:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^ user.cpp:136:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^ user.cpp:139:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^ user.cpp:171:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^ user.cpp:174:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^ user.cpp:206:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^ user.cpp:209:25: warning: unused variable ‘a’ [-Wunused-variable] int a; ^