/in/foo.c: In function 'main':
/in/foo.c:7:16: warning: right-hand operand of comma expression has no effect [-Wunused-value]
    7 |         for(a=2,a<n,a++)
      |                ^
/in/foo.c:7:24: error: expected ';' before ')' token
    7 |         for(a=2,a<n,a++)
      |                        ^
      |                        ;
/in/foo.c:7:24: error: expected expression before ')' token
/in/foo.c:8:17: warning: right-hand operand of comma expression has no effect [-Wunused-value]
    8 |         {for(i=1,i<=a,i++)
      |                 ^
/in/foo.c:8:26: error: expected ';' before ')' token
    8 |         {for(i=1,i<=a,i++)
      |                          ^
      |                          ;
/in/foo.c:8:26: error: expected expression before ')' token
/in/foo.c:9:10: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
    9 |         {if (a%i==0);
      |          ^~
/in/foo.c:10:10: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   10 |          sum=sum+i;
      |          ^~~