package main

import "fmt"

func main() {
	var S string
	fmt.Scan(&S)
	ans := 101
	for i := 0; i < len(S); i++ {
		if S[i] == 'c' {
			for j := i + 1; j < len(S); j++ {
				if S[j] == 'w' {
					for k := j + 1; k < len(S); k++ {
						if S[k] == 'w' {
							ans = min(ans, k-i+1)
						}
					}
				}
			}
		}
	}
	if ans != 101 {
		fmt.Println(ans)
	} else {
		fmt.Println("-1")
	}
}
func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}