let buf = readLine()!.split(separator: " ").map { Int($0)! }
let (a, b, c, d) = (buf[0], buf[1], buf[2], buf[3])

let remine = (31 - a) + b
var ans = 0

if remine >= c {
  ans = 1
} else if remine >= d {
  ans = 2
} else {
  ans = 3
}

print(ans)