import java.util.*; public class Main { public static void main(String[] args) { // TODO code application logic here Scanner shuru=new Scanner(System.in); String shen = shuru.nextLine(); shen = shen.replaceAll("[^a-zA-Z]",""); char [] si = shen.toCharArray(); for(int i = 0;i < si.length;i ++) { if((int)si[i]>=65 && (int)si[i]<=90) { si[i]+=32; } else { if((int)si[i]>=97 && (int)si[i]<=122) { si[i]-=32; } else { ; } } } for(int i = 0;i < si.length;i ++) { System.out.print(si[i]); } } }