Mã chấm: 267901

Main.cc: In function ‘int main()’:
Main.cc:7:27: error: ‘A’ was not declared in this scope
     scanf("%d %d %d %d", &A, &B, &X, &Y);
                           ^
Main.cc:7:31: error: ‘B’ was not declared in this scope
     scanf("%d %d %d %d", &A, &B, &X, &Y);
                               ^
Main.cc:7:35: error: ‘X’ was not declared in this scope
     scanf("%d %d %d %d", &A, &B, &X, &Y);
                                   ^
Main.cc:7:39: error: ‘Y’ was not declared in this scope
     scanf("%d %d %d %d", &A, &B, &X, &Y);
                                       ^