foo.c: In function 'main':
foo.c:10:25: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   10 |         for(int a=2;a<=n,a++)
      |                         ^
foo.c:10:29: error: expected ';' before ')' token
   10 |         for(int a=2;a<=n,a++)
      |                             ^
      |                             ;
foo.c:12:33: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   12 |                 for(int b=2;b<=n,b++)
      |                                 ^
foo.c:12:37: error: expected ';' before ')' token
   12 |                 for(int b=2;b<=n,b++)
      |                                     ^
      |                                     ;
foo.c:7:13: warning: unused variable 'b' [-Wunused-variable]
    7 |         int b;
      |             ^

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