program ideone;

var
cnt: array[1..26, 1..26] of integer;
i, j, itf, its: integer;
c: char;
s: string;

begin
	for i := 1 to 26 do
		for j := 1 to 26 do
			cnt[i][j] := 0;
	
	read(s);
	
	for i := 1 to length(s) do
	begin
		if (s[i] = ',') or (s[i] = '.') then
		begin
			j := i - 1;
			
			while (j >= 1) and (s[j] <> ',') do
				j := j - 1;
			
			cnt[ord(s[j + 1]) - ord('a') + 1][ord(s[i - 1]) - ord('a') + 1] := 
			cnt[ord(s[j + 1]) - ord('a') + 1][ord(s[i - 1]) - ord('a') + 1] + 1;
		end;
	end;
	
	itf := 1;
	its := 1;
	
	for i := 1 to 26 do
		for j := 1 to 26 do
			if cnt[i][j] > cnt[itf][its] then
			begin
				itf := i;
				its := j;
			end;
	
	writeln(chr(itf + ord('a') - 1), ' ', chr(its + ord('a') - 1));
end.