#include <bits/stdc++.h>
using namespace std;
char ch[1100];
int n;
inline bool nextChar() {
  char c = getchar();
  for (; (c < 'a') || (c > 'z'); c = getchar())
    if (c == EOF) return false;
  ch[++n] = c;
  return true;
}
int main() {
  while (nextChar())
    ;
  for (int i = 1; i <= n; i++) putchar(ch[i]);
  for (int i = n; i >= 1; i--) putchar(ch[i]);
  putchar('\n');
  return 0;
}
