foo.cc: In function 'int main()':
foo.cc:19:26: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   19 |         while(t.find(" ")!=-1){
      |               ~~~~~~~~~~~^~~~
foo.cc:22:27: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   22 |         while(tt.find(" ")!=-1){
      |               ~~~~~~~~~~~~^~~~
foo.cc:27:22: 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]
   27 |         for(int i=0;i<s.size();i++){
      |                     ~^~~~~~~~~

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