foo.cc: In function 'int main()':
foo.cc:10:30: warning: variable 'id' set but not used [-Wunused-but-set-variable]
   10 |                 int mx = -1, id = 0;
      |                              ^~
foo.cc:18:2: error: expected '}' at end of input
   18 | }
      |  ^
foo.cc:5:12: note: to match this '{'
    5 | int main() {
      |            ^

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