foo.cc:4:1: error: expected initializer before 'int'
    4 | int x;
      | ^~~
foo.cc:5:1: error: 'cin' does not name a type
    5 | cin>>x;
      | ^~~
foo.cc:6:1: error: expected unqualified-id before 'for'
    6 | for(int x1=3;x1<=x/2;x1=x1+2)
      | ^~~
foo.cc:6:14: error: 'x1' does not name a type
    6 | for(int x1=3;x1<=x/2;x1=x1+2)
      |              ^~
foo.cc:6:22: error: 'x1' does not name a type
    6 | for(int x1=3;x1<=x/2;x1=x1+2)
      |                      ^~

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