#include<stdio.h>
#include<algorithm>
using namespace std;
long long Mod = 1000000007, K, F[2010000], Inv[1010000], InvF[1010000], D[1010000], Po[1010000];
int n;
long long GetInv(long long a){
int b = Mod-2;
long long r = 1;
while(b){
if(b&1)r=r*a%Mod;
a=a*a%Mod;b>>=1;
}
return r;
}
int main(){
int i;
scanf("%d%lld",&n,&K);
Po[0]=F[0]=InvF[0]=1;
for(i=1;i<=2000000;i++)F[i] = F[i-1]*i%Mod;
for(i=1;i<=1000000;i++){
Po[i] = Po[i-1]*K%Mod;
Inv[i] = GetInv(i);
InvF[i] = InvF[i-1]*Inv[i]%Mod;
}
D[1] = K;
long long tp;
for(i=1;i<n;i++){
if(i%2==0)tp = F[i]*InvF[i/2]%Mod*InvF[i/2]%Mod*Inv[i/2+1]%Mod*Po[i/2]%Mod;
else tp = 0;
D[i+1] = ((D[i]-tp+Mod)%Mod*(K+1)%Mod + tp*K)%Mod;
}
printf("%lld\n",D[n]);
}
