import strutils, sequtils, algorithm
var heart: array[10, int]
heart.fill(1)
let N = stdin.readLine.parseInt

for _ in 0 ..< N:
  let t = stdin.readLine.split
  for i in 0 ..< 4:
    heart[t[i].parseInt] *= [0, 2][int(t[^1] == "YES")]

echo heart.find(heart.max)