foo.cc: In function 'int main()':
foo.cc:6:8: warning: 'B' may be used uninitialized in this function [-Wmaybe-uninitialized]
    6 |  int A,B,n,m,a,b,num;
      |        ^
foo.cc:15:7: warning: 'A' may be used uninitialized in this function [-Wmaybe-uninitialized]
   15 |    a=n%10;
      |      ~^~~

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