package main

import "fmt"

func main() {
	var s string
	fmt.Scan(&s)

	ans := -1
	flg := false

	for i := 0; i < len(s)-2; i++ {
		if s[i] == 'c' {
			for j := i + 1; j < len(s)-1; j++ {
				if s[j] == 'w' {
					for k := j + 1; k < len(s); k++ {
						if s[k] == 'w' {
							tmp := k - i + 1
							if !flg || tmp < ans {
								ans = tmp
								flg = true
							}
						}
					}
				}
			}
		}
	}
	fmt.Println(ans)
}