foo.c: In function 'main':
foo.c:10:20: warning: iteration 9 invokes undefined behavior [-Waggressive-loop-optimizations]
   10 |         {if(b+30>=a[i]) c=c+1;
      |                   ~^~~
foo.c:9:18: note: within this loop
    9 |         for(i=1;i<=10;i++)
      |                 ~^~~~

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