package main

import (
	"fmt"
	"strings"
)

func main() {
	var S string
	fmt.Scan(&S)
	password := ""
	for i := 0; i < len(S); i++ {
		s := string(S[i])
		if "a" <= s && s <= "z" {
			password += strings.ToUpper(s)
		} else {
			password += strings.ToLower(s)
		}
	}
	fmt.Println(password)
}