using System; using System.Collections.Generic; using System.Collections; using System.Collections.Specialized; using System.Linq; using System.Text; using System.IO; using System.Reflection; using static System.Math; using System.Numerics; static class Program{ const int mod=(int)1e9+7; const long inf=long.MaxValue-1; static List>[] li; static bool[] b; static Mint[] d; static long x; static void Main(){ Sc sc=new Sc(); var s=sc.Ia; var g=new int[s[1]][]; int n=s[0],m=n-1; x=s[2]; for(int i = 0;iu[2]-v[2]); Uf uf=new Uf(n+1); li=new List>[n+1]; b=new bool[n+1]; d=new Mint[n+1]; for(int i=1;i<=n;i++){ li[i]=new List>(); } for(int i = 0;i0){ if((e&1)>0){r*=x;r%=mod;} x=(x*x)%mod; e>>=1; } return r; } } public struct Mint{ const int mod=(int)1e9+7; private long d; public Mint(long d){this.d=d;} public static implicit operator Mint(long d){return new Mint(d%mod);} public static implicit operator bool(Mint d){return (int)d!=0;} public static explicit operator long(Mint d){return d.d;} public override string ToString(){return d.ToString();} public static Mint operator+(Mint a,long b){a.d=(a.d+b)%mod;return a;} public static Mint operator+(Mint a,Mint b){a.d=(a.d+b.d)%mod;return a;} public static Mint operator-(Mint a,long b){a.d=(mod+a.d-b)%mod;return a;} public static Mint operator-(Mint a,Mint b){a.d=(mod+a.d-b.d)%mod;return a;} public static Mint operator*(Mint a,long b){a.d=(a.d*b)%mod;return a;} public static Mint operator*(Mint a,Mint b){a.d=(a.d*b.d)%mod;return a;} public static Mint operator/(Mint a,long b){a.d=(a.d*Mi(b))%mod;return a;} public static Mint operator/(Mint a,Mint b){a.d=(a.d*Mi(b.d))%mod;return a;} private static long Mi(long a){ a=(a+mod)%mod; long b=mod,u=1,v=0; while(b>0){ long t=a/b; a-=t*b;(a,b)=(b,a); u-=t*v;(u,v)=(v,u); } u%=mod; if(u<0){u+=mod;} return u%mod; } } public class Uf{ private int[] arr,hi; public int all; public Uf(int n){ arr=new int[n]; hi=new int[n]; all=n; for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i(int n,Func f){var a=new T[n];for(int i=0;i