foo.cc: In function ‘int main()’:
foo.cc:7:22: warning: comparison of integer expressions of different signedness: ‘int’ and ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’} [-Wsign-compare]
    7 |         for(int i=0;i<s.size();i++)
      |                     ~^~~~~~~~~
foo.cc:7:9: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation]
    7 |         for(int i=0;i<s.size();i++)
      |         ^~~
foo.cc:9:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘for’
    9 |                 cout<<ans;
      |                 ^~~~