func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, b, m;   int a[100009], sum[100009];   map<int, int> h;   int main() {     cin >> b >> m >> n;     for (int i = 1; i <= n; i++) {       cin >> a[i];       sum[i] = (sum[i - 1] + a[i]) % (b - 1);     }     long long zero = 0, t = 0;     for (int i = 1; i <= n; i++) {       if (a[i] == 0)         t++;       else {         zero += 1ll * t * (t + 1) / 2;         t = 0;       }     }     if (t) zero += 1ll * t * (t + 1) / 2;     if (m == 0) {       cout << zero << endl;       return 0;     }     long long ans = 0;     h[0]++;     for (int i = 1; i <= n; i++) {       int t = ((sum[i] - m) % (b - 1) + (b - 1)) % (b - 1);       ans += h[t];       h[sum[i]]++;     }     if (m == b - 1) ans -= zero;     cout << ans << endl;   }   