#include<iostream> 
#include<cmath>
#include<iomanip>
#include <cstring>
using namespace std;
int INF=0x3f3f3f3f;
const int N=1e5+10;
int ans;
char a[N];
int main()
{
	cin.getline(a,255);
	int len=strlen(a);
	for(int i=0;i<=len-1;i++)
	{
		if(a[i]<=90 && a[i]>=65)
		{
			a[i]+=32;
			cout<<a[i];
		}
		else if(a[i]<=122 && a[i]>=97)
		{
			a[i]-=32;
			cout<<a[i];
		}
		else{
			cout<<a[i];
		}
	}
	return 0;
}