#include<cstdio>#include<cstring>#include<algorithm>#include<set>#include<bits/stdc++.h>usingnamespace std;typedeflonglong ll;#define space putchar(' ')#define enter putchar('\n')typedef pair<int,int> PII;constint mod=1e4+7;constint N=2e6+10;constint inf=0x7f7f7f7f;
ll gcd(ll a,ll b){return b==0?a:gcd(b,a%b);}
ll lcm(ll a,ll b){return a*(b/gcd(a,b));}template<classT>voidread(T &x){char c;bool op =0;while(c =getchar(), c <'0'|| c >'9')if(c =='-')
op =1;
x = c -'0';while(c =getchar(), c >='0'&& c <='9')
x = x *10+ c -'0';if(op)
x =-x;}template<classT>voidwrite(T x){if(x <0)
x =-x,putchar('-');if(x >=10)write(x /10);putchar('0'+ x %10);}int fa[N];int n,k;
PII a[N],sum[N];int dp[50][50];intmain(){read(n),read(k);
dp[0][1]=1;for(int i=1;i<=k;i++){for(int j=1;j<=n;j++){if(j==1)
dp[i][j]=dp[i-1][n]+dp[i-1][j+1];elseif(j==n)
dp[i][j]=dp[i-1][n-1]+dp[i-1][1];else
dp[i][j]=dp[i-1][j-1]+dp[i-1][j+1];}}write(dp[k][1]);return0;}