Consider a linear function f(x) = Ax + B. Let's define g(0)(x) = x and g(n)(x) = f(g(n - 1)(x)) for n > 0. For the given integer values A, B, n and x find the value of g(n)(x) modulo 109 + 7.

Input

The only line contains four integers A, B, n and x (1 ≤ A, B, x ≤ 109, 1 ≤ n ≤ 1018) — the parameters from the problem statement.

Note that the given value n can be too large, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.

Output

Print the only integer s — the value g(n)(x) modulo 109 + 7.

Examples

Input

3 4 1 1


Output

7


Input

3 4 2 1


Output

25


Input

3 4 3 1


Output

79

					import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.InputMismatchException;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Queue;
									public class Solution1 implements Runnable
									{
										static final long MAX = 1000000007L;
										static class InputReader
										{
											private InputStream stream;
											private byte[] buf = new byte[1024];
											private int curChar;
											private int numChars;
											private SpaceCharFilter filter;
											private BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
									 
											public InputReader(InputStream stream)
											{
												this.stream = stream;
											}
											
											public int read()
											{
												if (numChars==-1) 
													throw new InputMismatchException();
												
												if (curChar >= numChars)
												{
													curChar = 0;
													try 
													{
														numChars = stream.read(buf);
													}
													catch (IOException e)
													{
														throw new InputMismatchException();
													}
													
													if(numChars <= 0)				
														return -1;
												}
												return buf[curChar++];
											}
										 
											public String nextLine()
											{
												String str = "";
									            try
									            {
									                str = br.readLine();
									            }
									            catch (IOException e)
									            {
									                e.printStackTrace();
									            }
									            return str;
											}
											public int nextInt()
											{
												int c = read();
												
												while(isSpaceChar(c)) 
													c = read();
												
												int sgn = 1;
												
												if (c == '-') 
												{
													sgn = -1;
													c = read();
												}
												
												int res = 0;
												do 
												{
													if(c<'0'||c>'9') 
														throw new InputMismatchException();
													res *= 10;
													res += c - '0';
													c = read();
												}
												while (!isSpaceChar(c)); 
												
												return res * sgn;
											}
											
											public long nextLong() 
											{
												int c = read();
												while (isSpaceChar(c))
													c = read();
												int sgn = 1;
												if (c == '-') 
												{
													sgn = -1;
													c = read();
												}
												long res = 0;
												
												do 
												{
													if (c < '0' || c > '9')
														throw new InputMismatchException();
													res *= 10;
													res += c - '0';
													c = read();
												}
												while (!isSpaceChar(c));
													return res * sgn;
											}
											
											public double nextDouble() 
											{
												int c = read();
												while (isSpaceChar(c))
													c = read();
												int sgn = 1;
												if (c == '-') 
												{
													sgn = -1;
													c = read();
												}
												double res = 0;
												while (!isSpaceChar(c) && c != '.') 
												{
													if (c == 'e' || c == 'E')
														return res * Math.pow(10, nextInt());
													if (c < '0' || c > '9')
														throw new InputMismatchException();
													res *= 10;
													res += c - '0';
													c = read();
												}
												if (c == '.') 
												{
													c = read();
													double m = 1;
													while (!isSpaceChar(c)) 
													{
														if (c == 'e' || c == 'E')
															return res * Math.pow(10, nextInt());
														if (c < '0' || c > '9')
															throw new InputMismatchException();
														m /= 10;
														res += (c - '0') * m;
														c = read();
													}
												}
												return res * sgn;
											}
											
											public String readString() 
											{
												int c = read();
												while (isSpaceChar(c))
													c = read();
												StringBuilder res = new StringBuilder();
												do 
												{
													res.appendCodePoint(c);
													c = read();
												} 
												while (!isSpaceChar(c));
												
												return res.toString();
											}
										 
											public boolean isSpaceChar(int c) 
											{
												if (filter != null)
													return filter.isSpaceChar(c);
												return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
											}
										 
											public String next() 
											{
												return readString();
											}
											
											public interface SpaceCharFilter 
											{
												public boolean isSpaceChar(int ch);
											}
										}
									 	
										public static void main(String args[]) throws Exception
										{
											new Thread(null, new Solution1(),"Solution1",1<<26).start();
										}
										long gcd(long a, long b)
									    {
									        if (a == 0)
									            return b;
									         
									        return gcd(b%a, a);
									    }
									    // method to return LCM of two numbers
										 long lcm(long a, long b)
										    {
										        return (a*b)/gcd(a, b);
										    }
										final long bit = 60;
										public void run()
										{
											InputReader sc= new InputReader(System.in);
											PrintWriter w= new PrintWriter(System.out);
											long a=  sc.nextLong();
											long b = sc.nextLong();
											long c = sc.nextLong();
											long d = sc.nextLong();
											long ans = (binaryExponentiationIterative(a,c) * d)%MAX;
											long tmp = -1;
											if(a == 1){
												tmp = ((c % MAX) * b) %MAX;
											}else{
												tmp = ((binaryExponentiationIterative(a,c) - 1 + MAX) % MAX * b)%MAX;
												long e = a - 1;
												tmp = tmp * binaryExponentiationIterative(e , MAX - 2);
											}
											
										    ans = (ans + tmp)%MAX;
											w.println(ans);
											w.close();
										}
										long binaryExponentiationIterative(long x,long n){
											long result = 1;
											while(n > 0){
												if(n % 2 != 0)
													result = (result*x)%MAX;
												x = (x * x)%MAX;
												n = n/2;
											}
											return result;
										}
										static class Pair implements Comparable<Pair>{
											int a;
											long b;
											
											Pair(){}	
											Pair(int a,long b){
												this.a = a;
												this.b = b;
												
											}
											public int compareTo(Pair p){
												return Integer.compare(this.a,p.a);
											}
										}
						}