use std::io::Read;

fn main() {
	let mut s = String::new();
	std::io::stdin().read_to_string(&mut s).ok();
	let s: Vec<_> = s.lines().collect();
	let n = s[0].split(s[1]).count() as i32 - 1;
	println!("{}", if s[1].len() == 1 && n > 1 { -1 } else { n })
}