foo.cc: In function 'bool hui(long long int)':
foo.cc:5:8: error: 'n' was not declared in this scope
    5 |  int i=n,m=0;
      |        ^
foo.cc:7:3: error: 'm' was not declared in this scope
    7 |   m=m*10+i%10;
      |   ^
foo.cc:10:12: error: 'm' was not declared in this scope
   10 |  return n==m;
      |            ^
foo.cc: In function 'int main()':
foo.cc:17:4: error: 'sum' was not declared in this scope
   17 |    sum++;
      |    ^~~
foo.cc:20:5: error: 'sum' was not declared in this scope
   20 |  if(sum==0){
      |     ^~~
foo.cc:24:8: error: 'sum' was not declared in this scope
   24 |  cout<<sum<<endl;
      |        ^~~

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