foo.cc: In function 'int main()':
foo.cc:24:13: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   24 |    if(i-1>=0&&a[i]==a[i-1] || i+1<=n&&a[i]==a[i+1]-1)
      |       ~~~~~~^~~~~~~~~~~~~~
foo.cc:16:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:18:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |   scanf("%d",&a[i]);
      |   ~~~~~^~~~~~~~~~~~

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