foo.cc: In function 'int main()':
foo.cc:10:13: warning: iteration 69 invokes undefined behavior [-Waggressive-loop-optimizations]
   10 |         b[i]=b[i-1]*2;
      |         ~~~~^~~~~~~~~
foo.cc:9:20: note: within this loop
    9 |     for (int i=1; i<=70; i++)
      |                   ~^~~~

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Found 10 testcases.
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