foo.cc:1:5: error: expected unqualified-id before numeric constant
    1 | int 2,5,3;
      |     ^
foo.cc:2:1: error: 'cin\U0000ff1e\U0000ff1e2\U0000ff1e\U0000ff1e5\U0000ff1e\U0000ff1e3' does not name a type
    2 | cin＞＞2＞＞5＞＞3;
      | ^~~~~~~~~~~~~~~~~~
foo.cc:3:1: error: 'cout\U0000ff1c\U0000ff1c5\U0000ff1c\U0000ff1c' does not name a type
    3 | cout＜＜5＜＜" "＜＜3＜＜" "＜＜2＜＜endl；
      | ^~~~~~~~~~~~~

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