foo.cc:9:0: warning: ignoring #pragma warning  [-Wunknown-pragmas]
 #pragma warning(disable:4996)
 
foo.cc: In function 'int main()':
foo.cc:22:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int j = 0; j < s.length(); j++)
                   ~~^~~~~~~~~~~~
foo.cc:30:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int k = j; k < s.length(); k++)
                     ~~^~~~~~~~~~~~
foo.cc:45:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      if (k == s.length()-1)
          ~~^~~~~~~~~~~~~~~
foo.cc:109:7: warning: unused variable 'u' [-Wunused-variable]
   int u = 1;
       ^

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