func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long M = 1e9 + 9;   int n, m, a, b, k;   char s[100005];   long long ans, q;   inline long long f(char a) { return a ==  -  ? -1 : 1; }   inline long long fpow(long long a, long long b) {     long long r = 1;     for (; b; b >>= 1, a = (a * a) % M)       if (b & 1) r = (r * a) % M;     return r;   }   inline long long sum(long long a1, long long q, long long n) {     if (q == 1) return a1 * n % M;     long long p = (fpow(q, n) - 1 + M) % M;     long long qq = (q - 1 + M) % M;     qq = fpow(qq, M - 2);     return a1 * p % M * qq % M;   }   int main() {     scanf( %d %d %d %d , &n, &a, &b, &k);     q = b * fpow(a, M - 2) % M;     q = fpow(q, k);     m = (n + 1) / k;     scanf( %s , s);     if (n < k) {       for (int i = 0; i <= n; i++) {         long long t = fpow(a, n - i) * fpow(b, i) % M;         if (s[i] ==  - ) t = M - t;         (ans += t) %= M;       }       return printf( %lld n , ans), 0;     }     for (int i = 0; i < k; i++) {       long long x = sum(fpow(a, n - i) * fpow(b, i) % M, q, m);       if (s[i] ==  - ) x = M - x;       (ans += x) %= M;     }     printf( %lld n , ans);     return 0;   }   