foo.cc: In function ‘int main()’:
foo.cc:15:23: warning: ‘b’ may be used uninitialized [-Wmaybe-uninitialized]
   15 |         cout<<at%d*10+b;
      |                       ^
foo.cc:5:21: note: ‘b’ was declared here
    5 |         long long a,b,cnt=0,d;
      |                     ^