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.*;
import java.util.*;

public class C {

	static int mod = 1000000007;

	static int[][] matMul(int[][] A, int[][] B, int p, int q, int r) // C(p x r) = A(p x q) x (q x r) -- O(p x q x r)
	{
		int[][] C = new int[p][r];
		for (int i = 0; i < p; ++i)
			for (int j = 0; j < r; ++j)
				for (int k = 0; k < q; ++k) {
					C[i][j] += (A[i][k] * 1l * B[k][j]) % mod;
					C[i][j] %= mod;
				}
		return C;
	}

	/*
	 * 4. Square Matrix Exponentiation
	 */
	static int[][] matPow(int[][] base, long p) {
		int n = base.length;
		int[][] ans = new int[n][n];
		for (int i = 0; i < n; i++)
			ans[i][i] = 1;
		while (p != 0) {
			if ((p & 1) == 1)
				ans = matMul(ans, base, n, n, n);
			base = matMul(base, base, n, n, n);
			p >>= 1;
		}

		return ans;
	}

	
	public static void main(String args[]) throws Exception {
		Scanner sc = new Scanner(System.in);
		PrintWriter pw = new PrintWriter(System.out);

		int a=sc.nextInt();
		int b=sc.nextInt();
		long n=sc.nextLong();
		int x=sc.nextInt();
		
		int mat[][]=new int[][]{{a,1},{0,1}};
		int m[][]=new int[][]{{x},{b}};
		
		pw.print(matMul(matPow(mat, n), m, 2, 2, 1)[0][0]);
		pw.flush();
	}

	///////////////////////////////////////////////////////////////////////////////////////////

	static class tri {
		int x, y, z;

		public tri(int x, int y, int z) {
			this.x = x;
			this.y = y;
			this.z = z;
		}

	}

	static class pair implements Comparable<pair> {
		int x, y;
		boolean w, l;
		PriorityQueue<Long> pq;

		public pair(boolean a, boolean b) {
			w = a;
			l = b;
		}

		pair(int s, int d) {
			x = s;
			y = d;
		}

		@Override
		public int compareTo(pair p) {
			return y - p.y;
		}

		@Override
		public String toString() {
			return x + " " + y;

		}

	}

	static long mod(long ans, int mod) {
		return (ans % mod + mod) % mod;
	}

	static long gcd(long a, long b) {
		if (a == 0)
			return b;
		return gcd(b % a, a);
	}

	static long lcm(long a, long b) {
		return (a * b) / gcd(a, b);
	}

	public static int log(long k, int base) {
		int ans = 0;
		while (k + 1 > base) {
			ans++;
			k /= base;
		}
		return ans;
	}

	static long pow(long b, long e) {
		long ans = 1;
		while (e > 0) {
			if ((e & 1) == 1)
				ans = ((ans * 1l * b));
			e >>= 1;
			{

			}
			b = ((b * 1l * b));
		}
		return ans;
	}

	static long powmod(long r, long e, int mod) {
		long ans = 1;
		r %= mod;
		while (e > 0) {
			if ((e & 1) == 1)
				ans = (int) ((ans * 1l * r) % mod);
			e >>= 1;
			r = (int) ((r * 1l * r) % mod);
		}
		return ans;
	}

	static int ceil(int a, int b) {
		int ans = a / b;
		return a % b == 0 ? ans : ans + 1;
	}

	static long ceil(long a, long b) {
		long ans = a / b;
		return a % b == 0 ? ans : ans + 1;
	}

	static HashMap<Integer, Integer> compress(int a[]) {
		TreeSet<Integer> ts = new TreeSet<>();
		HashMap<Integer, Integer> hm = new HashMap<>();
		for (int x : a)
			ts.add(x);
		for (int x : ts) {
			hm.put(x, hm.size() + 1);
		}
		return hm;
	}

	// Returns nCr % p
	static int C[];

	static int nCrModp(int n, int r, int p) {
		if (r > n - r)
			r = n - r;
		if (C[r] != 0)
			return C[r];
		// The array C is going to store last
		// row of pascal triangle at the end.
		// And last entry of last row is nCr

		C[0] = 1; // Top row of Pascal Triangle

		// One by constructs remaining rows of Pascal
		// Triangle from top to bottom
		for (int i = 1; i <= n; i++) {

			// Fill entries of current row using previous
			// row values
			for (int j = Math.min(i, r); j > 0; j--)

				// nCj = (n-1)Cj + (n-1)C(j-1);
				C[j] = (C[j] + C[j - 1]) % p;
		}
		return C[r];
	}

	static class Scanner {
		StringTokenizer st;
		BufferedReader br;

		public Scanner(InputStream s) {
			br = new BufferedReader(new InputStreamReader(s));
		}

		public Scanner(String file) throws Exception {
			br = new BufferedReader(new FileReader(file));
		}

		public int[] intArr(int n) throws IOException {
			int a[] = new int[n];
			for (int i = 0; i < a.length; i++) {
				a[i] = nextInt();
			}
			return a;
		}

		public long[] longArr(int n) throws IOException {
			long a[] = new long[n];
			for (int i = 0; i < a.length; i++) {
				a[i] = nextLong();
			}
			return a;
		}

		public String next() throws IOException {
			while (st == null || !st.hasMoreTokens())
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}

		public int nextInt() throws IOException {
			return Integer.parseInt(next());
		}

		public long nextLong() throws IOException {
			return Long.parseLong(next());
		}

		public String nextLine() throws IOException {
			return br.readLine();
		}

		public double nextDouble() throws IOException {
			String x = next();
			StringBuilder sb = new StringBuilder("0");
			double res = 0, f = 1;
			boolean dec = false, neg = false;
			int start = 0;
			if (x.charAt(0) == '-') {
				neg = true;
				start++;
			}
			for (int i = start; i < x.length(); i++)
				if (x.charAt(i) == '.') {
					res = Long.parseLong(sb.toString());
					sb = new StringBuilder("0");
					dec = true;
				} else {
					sb.append(x.charAt(i));
					if (dec)
						f *= 10;
				}
			res += Long.parseLong(sb.toString()) / f;
			return res * (neg ? -1 : 1);
		}

		public boolean ready() throws IOException {
			return br.ready();
		}

	}

	public static void shuffle(int[] times2) {
		int n = times2.length;
		for (int i = 0; i < n; i++) {
			int r = i + (int) (Math.random() * (n - i));
			int tmp = times2[i];
			times2[i] = times2[r];
			times2[r] = tmp;
		}
	}

}