M = 0x3b9aca09
inv = lambda x: pow(x, M - 2, M)
n, a, b, k = map(int, input().split())
s = input()
c = inv(a) * b % M
q = pow(c, k, M)
m = (n + 1) // k
p = (pow(q, m, M) - 1) * inv(q - 1) % M if q - 1 else m
x = pow(a, n, M)
r = 0
for i in range(k):
r = (r + [-1, 1][s[i] == '+'] * x * p) % M
x = (x * c) % M
print(r)
1302. Deepest Leaves Sum | 1209. Remove All Adjacent Duplicates in String II |
994. Rotting Oranges | 983. Minimum Cost For Tickets |
973. K Closest Points to Origin | 969. Pancake Sorting |
967. Numbers With Same Consecutive Differences | 957. Prison Cells After N Days |
946. Validate Stack Sequences | 921. Minimum Add to Make Parentheses Valid |
881. Boats to Save People | 497. Random Point in Non-overlapping Rectangles |
528. Random Pick with Weight | 470. Implement Rand10() Using Rand7() |
866. Prime Palindrome | 1516A - Tit for Tat |
622. Design Circular Queue | 814. Binary Tree Pruning |
791. Custom Sort String | 787. Cheapest Flights Within K Stops |
779. K-th Symbol in Grammar | 701. Insert into a Binary Search Tree |
429. N-ary Tree Level Order Traversal | 739. Daily Temperatures |
647. Palindromic Substrings | 583. Delete Operation for Two Strings |
518. Coin Change 2 | 516. Longest Palindromic Subsequence |
468. Validate IP Address | 450. Delete Node in a BST |