foo.cc:4:1: error: expected initializer before '}' token
    4 | }
      | ^
foo.cc:4:1: error: expected declaration before '}' token
foo.cc:5:2: error: expected unqualified-id before 'if'
    5 |  if(n==1) return 0;
      |  ^~
foo.cc:6:2: error: expected unqualified-id before 'for'
    6 |  for(int i=2;i<=sqrt(n);i++)
      |  ^~~
foo.cc:6:14: error: 'i' does not name a type
    6 |  for(int i=2;i<=sqrt(n);i++)
      |              ^
foo.cc:6:25: error: 'i' does not name a type
    6 |  for(int i=2;i<=sqrt(n);i++)
      |                         ^
foo.cc:13:3: error: expected unqualified-id before 'return'
   13 |   return 1;
      |   ^~~~~~
foo.cc:14:1: error: expected declaration before '}' token
   14 | }
      | ^

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