foo.cc: In function 'int main()':
foo.cc:44:42: warning: iteration 501 invokes undefined behavior [-Waggressive-loop-optimizations]
   44 |                         passlength[i][j] = -1;
      |                         ~~~~~~~~~~~~~~~~~^~~~
foo.cc:42:32: note: within this loop
   42 |                 for(int j = 0;j<505;j++)
      |                               ~^~~~
foo.cc:44:42: warning: iteration 501 invokes undefined behavior [-Waggressive-loop-optimizations]
   44 |                         passlength[i][j] = -1;
      |                         ~~~~~~~~~~~~~~~~~^~~~
foo.cc:40:22: note: within this loop
   40 |         for(int i=0;i<505;i++)
      |                     ~^~~~
foo.cc:66:25: warning: 'maxpath' may be used uninitialized in this function [-Wmaybe-uninitialized]
   66 |         cout<<maxpath + 1;
      |                         ^

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