foo.c: In function 'main':
foo.c:15:32: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   15 |         {for(j=0,k=i;j<=(i-1)/2,k>=(i-1)/2+1;j++,k--)
      |                                ^
foo.c:21:30: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   21 |                           if(sum2=sum/2) printf("Yes");
      |                              ^~~~
foo.c:24:33: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   24 |            {for(j=0,k=i;j<=(i)/2,k>=(i)/2+1;j++,k--)
      |                                 ^
foo.c:30:30: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   30 |                           if(sum2=(sum-1)/2) printf("Yes");
      |                              ^~~~

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