package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

var sc = bufio.NewScanner(os.Stdin)

func main() {
	sc.Split(bufio.ScanWords)
	n, k := nextInt(), nextInt()
	s := nextLine()
	ns := make([]int, n)
	for i, r := range s {
		v, _ := strconv.Atoi(string(r))
		ns[i] = v
	}

	c, w := 0, 0
	for i, v := range ns {
		if w == 0 {
			c++
		} else {
			w--
		}
		if i+1 == k {
			fmt.Println(c)
			return
		}
		w += v
	}

	if w >= c {
		fmt.Println(c)
		return
	}

	k -= n
	c += (k / n) * (c - w)
	k %= n
	for i := 0; i < k; i++ {
		if w == 0 {
			c++
		} else {
			w--
		}
		w += ns[i]
	}
	fmt.Println(c)
}

func nextLine() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	i, _ := strconv.Atoi(nextLine())
	return i
}