foo.cc: In function 'int main()':
foo.cc:30:19: 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]
   30 |     for(int i=0; i<s.length(); i++) dp[i+1][(int)(s[i]-'0')%9]++;
      |                  ~^~~~~~~~~~~
foo.cc:31:21: 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]
   31 |     for(int i=1;  i <= s.length(); i++){
      |                   ~~^~~~~~~~~~~~~

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