foo.cc: In function 'int main()':
foo.cc:7:5: error: expected ';' before 'a'
    7 |  cin a>>b;
      |     ^~
      |     ;
foo.cc:7:2: warning: statement has no effect [-Wunused-value]
    7 |  cin a>>b;
      |  ^~~
foo.cc:8:12: error: expected '(' before 'b'
    8 |         if b==1,3,5,7,8,10,12;
      |            ^
      |            (
foo.cc:9:31: error: expected ';' before 'if'
    9 |                 cout<<31<<endl
      |                               ^
      |                               ;
   10 |         if b==4,6,9,11;
      |         ~~                     
foo.cc:11:31: error: expected ';' before 'else'
   11 |                 cout<<30<<endl
      |                               ^
      |                               ;
   12 |         else
      |         ~~~~                   
foo.cc:6:6: warning: unused variable 'a' [-Wunused-variable]
    6 |  int a,b;
      |      ^
foo.cc:6:8: warning: unused variable 'b' [-Wunused-variable]
    6 |  int a,b;
      |        ^

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