Problem:
Score : 100 points

Problem Statement

Given are two strings S and T consisting of lowercase English letters. Concatenate T and S in this order, without space in between, and print the resulting string.

Constraints

S and T are strings consisting of lowercase English letters.

The lengths of S and T are between 1 and 100 (inclusive).

Input

Input is given from Standard Input in the following format:

S T

Output

Print the resulting string.

Sample Input 1

oder atc

Sample Output 1

atcoder

When S = oder and T = atc, concatenating T and S in this order results in atcoder.

Sample Input 2

humu humu

Sample Output 2

humuhumu

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
typedef long long ll;
typedef pair<ll, ll> P;
const int MOD = 1000000007;
const int MAX = 5100000;
ll gcd(ll a, ll b) {
    return (b==0) ? a : gcd(b, a%b);
}

long long fac[MAX], finv[MAX], inv[MAX];

// テーブルを作る前処理
void COMinit() {
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for (int i = 2; i < MAX; i++){
        fac[i] = fac[i - 1] * i % MOD;
        inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
        finv[i] = finv[i - 1] * inv[i] % MOD;
    }
}

// 二項係数計算
ll COM(int n, int k){
    if (n < k) return 0;
    if (n < 0 || k < 0) return 0;
    return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

// 以下から
const int MAX_N = 100000;
struct Edge {
    int to;
    int id;
};


vector<int> to[100005];
int n;
vector<int> dist;
void dfs(int v, int d=0, int p=-1) {
    dist[v] = d;
    for (int u: to[v]) {
        if (u == p) continue;
        dfs(u, d+1, v);
    }
}

vector<int> calcDist(int s){
    dist = vector<int>(n);
    dfs(s);
    return dist;
}

int main() {
    string s,t; cin >> s >> t;
    stringstream ss;
    ss << t << s;
    cout << ss.str() << endl;
}