/in/foo.cc: In function 'int main()':
/in/foo.cc:14:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(a=0;a<=x.size();a=a+1)
          ~^~~~~~~~~~
/in/foo.cc:6:6: warning: unused variable 'y' [-Wunused-variable]
  int y[50];
      ^
/in/foo.cc:8:8: warning: unused variable 'b' [-Wunused-variable]
  int a,b,c,d,e,f,g=0;
        ^
/in/foo.cc:8:10: warning: unused variable 'c' [-Wunused-variable]
  int a,b,c,d,e,f,g=0;
          ^
/in/foo.cc:8:12: warning: unused variable 'd' [-Wunused-variable]
  int a,b,c,d,e,f,g=0;
            ^
/in/foo.cc:8:14: warning: unused variable 'e' [-Wunused-variable]
  int a,b,c,d,e,f,g=0;
              ^
/in/foo.cc:8:16: warning: unused variable 'f' [-Wunused-variable]
  int a,b,c,d,e,f,g=0;
                ^