from collections import defaultdict #####segfunc##### def segfunc(x, y): return max(x,y) ################# #####ide_ele##### ide_ele = 0 ################# class SegTree: """ init(init_val, ide_ele): 配列init_valで初期化 O(N) update(k, x): k番目の値をxに更新 O(logN) query(l, r): 区間[l, r)をsegfuncしたものを返す O(logN) """ def __init__(self, init_val, segfunc, ide_ele): """ init_val: 配列の初期値 segfunc: 区間にしたい操作 ide_ele: 単位元 n: 要素数 num: n以上の最小の2のべき乗 tree: セグメント木(1-index) """ n = len(init_val) self.segfunc = segfunc self.ide_ele = ide_ele self.num = 1 << (n - 1).bit_length() self.tree = [ide_ele] * 2 * self.num # 配列の値を葉にセット for i in range(n): self.tree[self.num + i] = init_val[i] # 構築していく for i in range(self.num - 1, 0, -1): self.tree[i] = self.segfunc(self.tree[2 * i], self.tree[2 * i + 1]) def update(self, k, x): """ k番目の値をxに更新 k: index(0-index) x: update value """ k += self.num self.tree[k] = x while k > 1: self.tree[k >> 1] = self.segfunc(self.tree[k], self.tree[k ^ 1]) k >>= 1 def query(self, l, r): """ [l, r)のsegfuncしたものを得る l: index(0-index) r: index(0-index) """ res = self.ide_ele l += self.num r += self.num while l < r: if l & 1: res = self.segfunc(res, self.tree[l]) l += 1 if r & 1: res = self.segfunc(res, self.tree[r - 1]) l >>= 1 r >>= 1 return res import sys #sys.setrecursionlimit(500000) def I(): return int(sys.stdin.readline().rstrip()) def MI(): return map(int,sys.stdin.readline().rstrip().split()) def TI(): return tuple(map(int,sys.stdin.readline().rstrip().split())) def LI(): return list(map(int,sys.stdin.readline().rstrip().split())) def S(): return sys.stdin.readline().rstrip() def LS(): return list(sys.stdin.readline().rstrip()) #for i, pi in enumerate(p): from collections import defaultdict,deque import bisect import itertools dic = defaultdict(int) d = deque() YN = ['No','Yes'] A = LS() N = len(A) for i in range(N+1): check = 1 for j in range(N): a = N+i-1-j if a >= N: continue if A[j] != A[a]: check = 0 break if check: ans = i+N break #print(ans) answer = A+[0]*(ans-N) #print(answer) for j in range(ans-N): answer[-j-1] = A[j] print("".join(answer))