foo.cc: In function 'int main()':
foo.cc:7:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(n==1)  
  ^~
foo.cc:9:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   if(n==2)
   ^~
foo.cc:11:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(n>=3)
  ^~
foo.cc:13:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   for(z=3;z<=n;z++)
   ^~~
foo.cc:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~

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