foo.cc: In function 'int main()':
foo.cc:9:11: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |  for(i=0;i<a.size();i++){
      |          ~^~~~~~~~~
foo.cc:22:6: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |  if(i==a.size()&&flag)cout<<'0';
      |     ~^~~~~~~~~~
foo.cc:5:14: warning: unused variable 'j' [-Wunused-variable]
    5 |  long long i,j,k,l,r,flag=1;
      |              ^
foo.cc:5:16: warning: unused variable 'k' [-Wunused-variable]
    5 |  long long i,j,k,l,r,flag=1;
      |                ^
foo.cc:5:18: warning: unused variable 'l' [-Wunused-variable]
    5 |  long long i,j,k,l,r,flag=1;
      |                  ^
foo.cc:5:20: warning: unused variable 'r' [-Wunused-variable]
    5 |  long long i,j,k,l,r,flag=1;
      |                    ^

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