package 洛谷.数组;
import java.util.Scanner;

public class B3674{
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String str=scan.nextLine();
        char[] arr=str.toCharArray();
        int f=0;
        for (int i = 0; i < arr.length; i++) {
            if(arr[i]==' '){
                f=0;
            }else{
                f++;
            }
            if(f%2==1&&arr[i]>='a'&&arr[i]<='z'){
                arr[i]-=32;
            }
             if(f%2==0&&arr[i]>='A'&&arr[i]<='Z'){
                arr[i]+=32;
            }
        }
        for (char c : arr) {
            System.out.print(c);
        }
    }
}