My code:

var
  a:array[1..1000]of string;
  b:array[1..1000]of integer;
  n,i,j,m,max:integer;
  s:string;
  c:boolean;
begin
  readln(n);
  for i:=1 to n do
    begin
      c:=true;
      readln(s);
      for j:=1 to m do
        if s=a[j]
          then begin
                 inc(b[j]);
                 c:=false;
                 break;
               end;
      if c then begin
                  inc(m);
                  a[m]:=s;
                  inc(b[m]);
                end;
    end;
  for i:=1 to n do
    if max<b[i]
      then max:=b[i];
  writeln(max);
end.

I know.
I understood that the wrong.^^

if c=true then begin