foo.cc: In function 'int main()':
foo.cc:18:23: error: 'end1' was not declared in this scope
   18 |      cout<<b<<"/"<<a<<end1;
      |                       ^~~~
foo.cc:19:10: warning: unused variable 'aa' [-Wunused-variable]
   19 |      int aa=a,bb=b;
      |          ^~
foo.cc:19:15: warning: unused variable 'bb' [-Wunused-variable]
   19 |      int aa=a,bb=b;
      |               ^~

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