foo.cc: In function 'int main()':
foo.cc:20:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |     for (int i = 0; i < s.size(); i++)
      |                     ~~^~~~~~~~~~
foo.cc:24:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |             for (j = 0, k = i; j < s1.size(); j++, k++)
      |                                ~~^~~~~~~~~~~
foo.cc:27:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |             if(j == s1.size() && (k == s.size() || s[k] == ' '))
      |                ~~^~~~~~~~~~~~
foo.cc:27:37: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |             if(j == s1.size() && (k == s.size() || s[k] == ' '))
      |                                   ~~^~~~~~~~~~~
foo.cc:36:29: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
   36 |         cout << c << " " << x <<endl;
      |                             ^

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