#include <iostream>
#include <vector>
#include <string>
#include <cstring>
#include <algorithm>
#include <sstream>
#include <map>
#include <set>
using namespace std;


#define REP(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) REP(i,0,n)

typedef long long ll;
typedef unsigned long long ull;
typedef long double lb;
/* ここからが本編 */


int main(void)
{
   int i,j,k,l;
   char s[105];
   scanf("%s",s);
   for(i = 0;s[i];i++) {
      if('a' <= s[i] && s[i] <= 'z') s[i] = toupper(s[i]);
      else if('A' <= s[i] && s[i] <= 'Z') s[i] = tolower(s[i]);
   }
   cout << s << endl;

   return 0;
}