/in/foo.cc: In function 'int main()':
/in/foo.cc:10:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(a=0;a<=x.size()-1;a=a+1)
          ~^~~~~~~~~~~~
/in/foo.cc:30:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(a=0;a<=x.size()-1;a=a+1)
          ~^~~~~~~~~~~~
/in/foo.cc:33:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(b=a+1;b<=x.size()-1;b=b+1)
             ~^~~~~~~~~~~~
/in/foo.cc:8:16: warning: unused variable 'c' [-Wunused-variable]
  long long a,b,c,d,e,f,max;
                ^
/in/foo.cc:8:20: warning: unused variable 'e' [-Wunused-variable]
  long long a,b,c,d,e,f,max;
                    ^
/in/foo.cc:8:22: warning: unused variable 'f' [-Wunused-variable]
  long long a,b,c,d,e,f,max;
                      ^