K好数

import java.util.Scanner;

public class Main{
    public static final int MOD=1000000007;
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        int K=scanner.nextInt();
        int L=scanner.nextInt();
        int[][] dp=new int[L][K];
        for(int j=0;j0][j]=1;
        }
        for(int i=1;ifor(int j=0;jfor(int x=0;xif(x!=j-1 && x!=j+1) {
                        dp[i][j]=dp[i][j]+dp[i-1][x];
                        dp[i][j]=dp[i][j]%MOD;
                    }
                }
            }
        }
        int sum=0;
        for(int j=1;j1][j];
            sum=sum%MOD;
        }
        System.out.println(sum);
        scanner.close();
    }
}