foo.cc: In function 'int main()':
foo.cc:5:11: error: expected unqualified-id before ';' token
    5 |   int a,b,;
      |           ^
foo.cc:7:12: warning: format '%d' expects argument of type 'int', but argument 2 has type 'int*' [-Wformat=]
    7 |   printf("%d,%d",&b,&a);
      |           ~^     ~~
      |            |     |
      |            int   int*
      |           %n
foo.cc:7:15: warning: format '%d' expects argument of type 'int', but argument 3 has type 'int*' [-Wformat=]
    7 |   printf("%d,%d",&b,&a);
      |              ~^     ~~
      |               |     |
      |               int   int*
      |              %n

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