foo.cc: In function 'int main()':
foo.cc:20:34: warning: for increment expression has no effect [-Wunused-value]
   20 |                 for(int i=2;i++;i<7)
      |                                 ~^~
foo.cc:20:30: warning: iteration 2147483645 invokes undefined behavior [-Waggressive-loop-optimizations]
   20 |                 for(int i=2;i++;i<7)
      |                             ~^~
foo.cc:20:30: note: within this loop

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