foo.cc: In function 'int main()':
foo.cc:10:23: warning: iteration 10000003 invokes undefined behavior [-Waggressive-loop-optimizations]
   10 |                 ans[i]=ans[i-1]*3+sum;
      |                 ~~~~~~^~~~~~~~~~~~~~~
foo.cc:8:22: note: within this loop
    8 |         for(int i=2;i<=10000005;i++)
      |                     ~^~~~~~~~~~

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Found 6 testcases.
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