using System; using System.Collections.Generic; using System.Collections; using System.Collections.Specialized; using System.Linq; using System.Text; using System.Text.RegularExpressions; using System.IO; using System.Reflection; using static System.Math; using System.Numerics; using System.Threading; using System.Runtime.CompilerServices; using System.Diagnostics; //using nint=System.Int32; static class Program{ const int mod=(int)1e9+7; static void Main(){ Sc sc=new Sc(); var n=sc.I; var a=sc.Ia; var g=new Mint[n]; g[n-1]=1; for(int i = n-2;i>=0;i--) { g[i]=g[i+1]*3; } Mint ans=0,p=1; for(int i = 0;i0){ 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 Sc{ public int I{get{return int.Parse(Console.ReadLine());}} public long L{get{return long.Parse(Console.ReadLine());}} public double D{get{return double.Parse(Console.ReadLine());}} public string S{get{return Console.ReadLine();}} public int[] Ia{get{return Array.ConvertAll(Console.ReadLine().Split(),int.Parse);}} public long[] La{get{return Array.ConvertAll(Console.ReadLine().Split(),long.Parse);}} public double[] Da{get{return Array.ConvertAll(Console.ReadLine().Split(),double.Parse);}} public string[] Sa{get{return Console.ReadLine().Split();}} public object[] Oa{get{return Console.ReadLine().Split();}} public int[] Ia2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),int.Parse);}} public int[] Ia3(string a,string b){return Array.ConvertAll((a+Console.ReadLine()+b).Split(),int.Parse);} public int[] Ia3(int a){return Array.ConvertAll((Console.ReadLine()+" "+a.ToString()).Split(),int.Parse);} public long[] La2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),long.Parse);}} public long[] La3(string a,string b){return Array.ConvertAll((a+Console.ReadLine()+b).Split(),long.Parse);} public long[] La3(int a){return Array.ConvertAll((Console.ReadLine()+" "+a.ToString()).Split(),long.Parse);} public double[] Da2{get{return Array.ConvertAll(("0 "+Console.ReadLine()+" 0").Split(),double.Parse);}} public double[] Da3(string a,string b){return Array.ConvertAll((a+Console.ReadLine()+b).Split(),double.Parse);} public T[] Arr(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(){var s=Console.ReadLine().Split();return (Ct(s[0]),Ct(s[1]));} public (T,T,T) Tp3(){var s=Console.ReadLine().Split();return (Ct(s[0]),Ct(s[1]),Ct(s[2]));} public (T,T,T,T) Tp4(){var s=Console.ReadLine().Split();return (Ct(s[0]),Ct(s[1]),Ct(s[2]),Ct(s[3]));} public (T1,T2) Tp2(){var s=Console.ReadLine().Split();return (Ct(s[0]),Ct(s[1]));} public (T1,T1,T2) Tp3(){var s=Console.ReadLine().Split();return (Ct(s[0]),Ct(s[1]),Ct(s[2]));} private T Ct(string s){return (T)Convert.ChangeType(s,typeof(T));} }