Baekjoon #14712

#include<bits/stdc++.h>

using namespace std;

int N, M, Map[33][33]; // 1-index
int answer = 0;

bool check(int y, int x) {
    return Map[y-1][x] && Map[y][x-1] && Map[y-1][x-1];
}

void go(int usedCnt) {
    if(usedCnt == N * M) {
        answer ++;
        return ;
    }

    int y = usedCnt / M + 1;
    int x = usedCnt % M + 1;

    go(usedCnt + 1);
    if(!check(y, x)) {
        Map[y][x] = 1;
        go(usedCnt + 1);
        Map[y][x] = 0;
    }
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    
    cin >> N >> M;
    go(0);
    cout << answer;

    return 0;
}

import java.io.*;
import java.util.*;
import java.lang.*;

public class Main {
    static int [][]map;
    static int N, M;
    static int answer;
    static public void main(String[] args) {
        FastReader rd = new FastReader();

        N = rd.nextInt();
        M = rd.nextInt();

        map = new int[N + 1][M + 1]; // 1-index
        
        dfs(0);

        System.out.println(answer);
    }

    static void dfs(int cnt) {
        if(cnt == N * M) {
            answer ++;
            return ;
        }
        int y = cnt / M + 1;
        int x = cnt % M + 1;
        
        if(map[y - 1][x] == 1 && map[y][x - 1] == 1 && map[y - 1][x - 1] == 1) { // 현재 놓을 수 없는 곳
            dfs(cnt + 1);
        }
        else {
            dfs(cnt + 1); // 선택 안하고 다음껄 볼 경우
            map[y][x] = 1;
            dfs(cnt + 1); // 선택 하고 다음껄 볼 경우
            map[y][x] = 0;
        }
    }

    static class FastReader {
        BufferedReader br;
        StringTokenizer st;

        public FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while(st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() { return Integer.parseInt(next()); }
        long nextLong() { return Long.parseLong(next()); }
        double nextDouble() { return Double.parseDouble(next()); }
        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            }
            catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
}

import sys

def input():
    return sys.stdin.readline().rstrip()

N, M = map(int, input().split())

# 1-index
Map = [ [ 0 for _ in range(M + 1) ] for __ in range(N + 1) ]
answer = 0

def dfs(cnt):
    global answer
    if cnt == N * M:
        answer += 1
        return
    
    y = cnt // M + 1
    x = cnt  % M + 1
    
    dfs(cnt + 1)
    if Map[y - 1][x] == 0 or Map[y][x - 1] == 0 or Map[y - 1][x - 1] == 0: # 만약 놓을 수 있는 곳이라면
        Map[y][x] = 1
        dfs(cnt + 1)
        Map[y][x] = 0

dfs(0)
print(answer)