foo.cpp: In function 'int main()':
foo.cpp:26:6: error: request for member 'clear' in 'ss', which is of pointer type 'std::stringstream* {aka std::basic_stringstream<char>*}' (maybe you meant to use '->' ?)
   ss.clear();
      ^
foo.cpp:32:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (i = 0;i <= t.length() - 1;i++)
                ^