foo.cc: In function 'int main()':
foo.cc:10:6: error: 'num' was not declared in this scope; did you mean 'enum'?
   10 |  for(num=2;num<abc/2;num++)
      |      ^~~
      |      enum
foo.cc:14:4: error: 'count' was not declared in this scope
   14 |    count=1;
      |    ^~~~~
foo.cc:20:19: error: 'count' was not declared in this scope
   20 |  if ((b+c)%10==a&&count==0)
      |                   ^~~~~
foo.cc:8:16: warning: unused variable 'countnum' [-Wunused-variable]
    8 |  int abc,a,b,c,countnum;
      |                ^~~~~~~~

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