foo.cc: In function 'int main()':
foo.cc:17:15: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |   int n; scanf("%d",&n);
      |          ~~~~~^~~~~~~~~
foo.cc:24:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   24 |   scanf("%d",&x);
      |   ~~~~~^~~~~~~~~
foo.cc:19:31: warning: iteration 2000009 invokes undefined behavior [-Waggressive-loop-optimizations]
   19 |  for(int i=1; i<=N; i++) p[i] = i;
      |                          ~~~~~^~~
foo.cc:19:16: note: within this loop
   19 |  for(int i=1; i<=N; i++) p[i] = i;
      |               ~^~~

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