foo.cc: In function 'int main()':
foo.cc:5:10: error: expected initializer before '>=' token
     int A>=1,B<=50000;
          ^~
foo.cc:6:7: error: 'A' was not declared in this scope
  cin>>A B>>endl;
       ^
foo.cc:7:10: error: 'B' was not declared in this scope
  cout<<A*B<<endl;
          ^

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