/in/foo.cc: In function 'void res()':
/in/foo.cc:10:22: warning: iteration 1000004 invokes undefined behavior [-Waggressive-loop-optimizations]
   10 |                 dp[i]=i;
      |                 ~~~~~^~
/in/foo.cc:8:23: note: within this loop
    8 |         for (int i=1;i<=N;i++)
      |                      ~^~~