# frozen_string_literal: true

S = gets.strip
T = gets.strip

unless S.include?(T)
  puts(0)
  exit
end

if T.length == 1
  puts(-1)
  exit
end

T2 = T.chars

count = 0
prev = nil
S.chars.each_cons(T2.size).map.with_index do |sub, index|
  (index..index + T2.size - 1).to_a if sub == T2
end.compact.each do |range|
  unless range.include?(prev)
    count += 1
    prev = range.last
  end
end

count = count * 2 - 1 if T.size == 2 && T2.uniq.size == 1

puts(count)