/in/foo.cc: In function 'void yuchuli()':
/in/foo.cc:11:43: warning: iteration 333665 invokes undefined behavior [-Waggressive-loop-optimizations]
   11 |         for(int i=5;i<=1001000;i+=3) dp[i]=dp[i-2]*2%N;
      |                                      ~~~~~^~~~~~~~~~~~
/in/foo.cc:11:22: note: within this loop
   11 |         for(int i=5;i<=1001000;i+=3) dp[i]=dp[i-2]*2%N;
      |                     ~^~~~~~~~~