foo.cc: In function 'Listnode* Insert(int*, int)':
foo.cc:11:12: error: invalid conversion from 'int' to 'Listnode*' [-fpermissive]
     return 3 353;
            ^
foo.cc:11:14: error: expected ';' before numeric constant
     return 3 353;
              ^~~
foo.cc:11:17: warning: statement has no effect [-Wunused-value]
     return 3 353;
                 ^

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