n = gets.chomp.to_i
an = [""] * n
ans = []
while i = gets
  s = i.chomp.split
  n.times{|i|an[i] += " "+s[i]}
end
n.times{|i|ans << an[i].split.count("nyanpass")}
p ans.count(ans.max) > 1 ? -1 : ans.index(ans.max)+1