#include <bits/stdc++.h>
using namespace std;
int main(){
	char a[1000];
	gets(a);
	int i,n;
	for(n=1;n<=strlen(a);n++){
		if(a[n-1]!=' ')
			if(a[n-1]>='A'&&a[n-1]<='Z'){
				cout<<char(a[n-1]+32);break;}
			else{
				cout<<char(a[n-1]-32);break;}
	}	
	for(;n<=strlen(a);n++){
		if(a[n]==' '&&a[n+1]!=' ')
			if(a[n+1]>='A'&&a[n+1]<='Z')
				cout<<char(a[n+1]+32);
			else
				cout<<char(a[n+1]-32);
	}
	
	return 0;
	}

/**************************************************************
	Problem: 1100
	User: fzy001
	Language: C++
	Result: Wrong Answer
****************************************************************/