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
(a,b,n,x)=input().split(' ')
a,b,n,x=int(a),int(b),int(n),int(x)
if a==1:
	print((x+n*b)%(10**9+7))
else:
	print(((pow(a,n,10**9+7)*x)%(10**9+7)+(((pow(a,n,10**9+7)-1)*b)%(10**9+7)*pow(a-1,10**9+5,10**9+7))%(10**9+7))%(10**9+7))
