program mn;
uses crt;
var f:text;
s:string;
i,z:integer;
BEGIN ClrSCr;
Assign(f,'text.txt');
reset(f);
While not eof(f)do begin readln(f,s);
if s[1]+s[2]=s[length(s)-1]+s[length(s)] then inc(z);
end;
close(f);
append(f);
writeln(f,z);
close(f);
readln;
END.