foo.cc: In function 'int main()':
foo.cc:9:32: 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(long long int i=0;i<s.size()-1;i+=2)
| ~^~~~~~~~~~~
foo.cc:22:26: 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 | else if(i<s.size()-1)
| ~^~~~~~~~~~~
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