foo.cc: In constructor 'seq::seq(int, int)':
foo.cc:8:6: warning: 'seq::size' will be initialized after [-Wreorder]
    8 |  int size;
      |      ^~~~
foo.cc:7:6: warning:   'int seq::n' [-Wreorder]
    7 |  int n;
      |      ^
foo.cc:10:2: warning:   when initialized here [-Wreorder]
   10 |  seq(int size=0,int n=0):size(size),n(n){
      |  ^~~

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