foo.cc:1:1: error: 'import' does not name a type
    1 | import java.io.*;
      | ^~~~~~
foo.cc:1:1: note: C++20 'import' only available with '-fmodules-ts'
foo.cc:2:1: error: 'import' does not name a type
    2 | import java.util.*;
      | ^~~~~~
foo.cc:2:1: note: C++20 'import' only available with '-fmodules-ts'
foo.cc:3:1: error: 'import' does not name a type
    3 | import java.math.*;
      | ^~~~~~
foo.cc:3:1: note: C++20 'import' only available with '-fmodules-ts'
foo.cc:5:1: error: expected unqualified-id before 'public'
    5 | public class Main {
      | ^~~~~~

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