foo.cc: In function 'int main()':
foo.cc:30:19: warning: 'b1' may be used uninitialized [-Wmaybe-uninitialized]
   30 |         cout<<b1<<" "<<a1;
      |                   ^~~
foo.cc:14:26: note: 'b1' was declared here
   14 |         int n,m,a1,a2,a3,b1,b2,b3;
      |                          ^~
foo.cc:30:24: warning: 'a1' may be used uninitialized [-Wmaybe-uninitialized]
   30 |         cout<<b1<<" "<<a1;
      |                        ^~
foo.cc:14:17: note: 'a1' was declared here
   14 |         int n,m,a1,a2,a3,b1,b2,b3;
      |                 ^~

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