/in/foo.cc: In function 'int main()':
/in/foo.cc:22:13: warning: iteration 10 invokes undefined behavior [-Waggressive-loop-optimizations]
  ans=ans+a[i];
          ~~~^
/in/foo.cc:21:11: note: within this loop
  for(i=1;i<=11;i++)
          ~^~~~
/in/foo.cc:19:6: warning: iteration 10 invokes undefined behavior [-Waggressive-loop-optimizations]
  a[i]=0;
  ~~~~^~
/in/foo.cc:18:11: note: within this loop
  for(i=1;i<=11;i++)
          ~^~~~