foo.cc:1:1: error: 'package' does not name a type
    1 | package main
      | ^~~~~~~
foo.cc:14:1: error: 'func' does not name a type
   14 | func longestSubstring1(s string, k int) int {
      | ^~~~
foo.cc:38:1: error: 'func' does not name a type
   38 | func getMax(a, b int) int {
      | ^~~~
foo.cc:46:1: error: 'func' does not name a type
   46 | func longestSubstring2(s string, k int) int {
      | ^~~~

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