#include <iostream>
using namespace std;
int main() {
int n, k;
cin>>n>>k;
int dp[n+1][k+1]={};
for(int i=1; i<=k; i++)
dp[1][i]=1;
for(int len=2; len<=n; len++){
if(len%2==0){
for(int i=1; i<=k; i++){
for (int j=i+1; j<=k; j++){
dp[len][i]+=dp[len-1][j];
}
}
} else {
for(int i=1; i<=k; i++){
for(int j=1; j<=i-1; j++){
dp[len][i]+=dp[len-1][j];
}
}
}
}
int ans=0;
for(int i=1; i<=k; i++)
ans+=dp[n][i];
if(n>1) ans*=2;
cout<<ans<<endl;
return 0;
}
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