---

Lỗi biên dịch:

Main.cc: In function ‘int main()’:
Main.cc:8:5: error: ‘vo’ was not declared in this scope
     vo = 1;
     ^~
Main.cc:9:5: error: ‘but’ was not declared in this scope
     but = 3;
     ^~~
Main.cc:9:5: note: suggested alternative: ‘putw’
     but = 3;
     ^~~
     putw
Main.cc:10:5: error: ‘gia_vo’ was not declared in this scope
     gia_vo = 4;
     ^~~~~~
Main.cc:10:5: note: suggested alternative: ‘gid_t’
     gia_vo = 4;
     ^~~~~~
     gid_t
Main.cc:11:5: error: ‘gia_but’ was not declared in this scope
     gia_but = 1;
     ^~~~~~~
Main.cc:11:5: note: suggested alternative: ‘gid_t’
     gia_but = 1;
     ^~~~~~~
     gid_t