#include<iomanip>
#include<cmath>
#include<cstring>
using namespace std;
const int N=1e3+10;
const int INF=0x3f3f3f3f;
char a[N];
int ans;
int main()
{
	cin.getline(a,501);
	int len=strlen(a);
	for(int i=0;i<len;i++)
	{
		if(a[i]>='A'&&a[i]<='Z')
		{
			a[i]+=32;
			cout<<a[i];
	    }
		else if(a[i]>='a'&&a[i]<='z') 
		{
			a[i]-=32;
			cout<<a[i];
		}
		else
		cout<<a[i];
	}
	return 0;
}