#include <bits/stdc++.h>
#define endl '\n'
#define int long long
#define lint long long
#define pii pair<int, int>
#define FOR(i, a, b) for(int i = (a); i < (b); ++i)
#define FORR(i, a, b) for(int i = (a); i > (b); --i)
#define REP(i, n) FOR(i, 0, n)
#define SZ(v) ((int)v.size())
#define ZERO(a) memset(a, 0, sizeof(a))
#define MINUS(a) memset(a, 0xff, sizeof(a))
#define FILLINF(a) memset(a, 0x3f, sizeof(a))
#define POW(n) (1LL << (n))
#define POPCNT(n) (__builtin_popcount(n))
#define IN(i, a, b) ((a) <= (i) && (i) <= (b))
using namespace std;
template <typename T> inline bool CHMIN(T& a, T b) { if(a > b) { a = b; return 1; } return 0; }
template <typename T> inline bool CHMAX(T& a, T b) { if(a < b) { a = b; return 1; } return 0; }
template <typename T> inline void SORT(T& a) { sort(begin(a), end(a)); }
template <typename T> inline void REV(T& a) { reverse(begin(a), end(a)); }
template <typename T> inline void UNI(T& a) { sort(a.begin(), a.end()); a.erase(unique(a.begin(), a.end()), a.end()); }
template <typename S, typename T> inline T LB(S& v, T a) { return *lower_bound(begin(v), end(v), a); }
template <typename S, typename T> inline int LBP(S& v, T a) { return lower_bound(begin(v), end(v), a) - begin(v); }
template <typename S, typename T> inline T UB(S& v, T a) { return *upper_bound(begin(v), end(v), a); }
template <typename S, typename T> inline int UBP(S& v, T a) { return upper_bound(begin(v), end(v), a) - begin(v); }
template <typename S, typename T> ostream& operator << (ostream& os, const pair<S, T>& p) { os << p.first << " " << p.second; return os; }
template <typename S, typename T> istream& operator >> (istream& is, pair<S, T>& p) { is >> p.first >> p.second; return is; }
template <typename T> ostream& operator << (ostream& os, const vector<T>& v) { for (int i = 0; i < v.size(); ++i) { if (i) os << " "; os << v[i]; } return os; }
template <typename T> istream& operator >> (istream& is, vector<T>& v) { for(T& in : v) is >> in; return is; }
template <typename T = int> vector<T> make_v(size_t a) { return vector<T>(a); }
template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) { return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...)); }
template <typename T, typename V> typename enable_if<is_class<T>::value == 0>::type fill_v(T& t, const V& v) { t = v; }
template <typename T, typename V> typename enable_if<is_class<T>::value != 0>::type fill_v(T& t, const V& v) { for(auto &e : t) fill_v(e, v); }
const double PI = 3.14159265358979323846;
const double EPS = 1e-10;
const lint INF = 0x3f3f3f3f3f3f3f3f;
const lint MOD = 1000000007;

template <class OM>
class DualSegmentTree {
    void init(int _n) {
        for (n = 1, lev = 0; n < _n; n <<= 1, ++lev);
        lz.assign(n << 1, u0);
    }

    inline void propagate(int k) {
        if (lz[k] == u0) return;
        lz[(k << 1) | 0] = h(lz[(k << 1) | 0], lz[k]);
        lz[(k << 1) | 1] = h(lz[(k << 1) | 1], lz[k]);
        lz[k] = u0;
    }

    inline void thrust(int k) {
        for (int i = lev; i > 0; --i) propagate(k >> i);
    }

public:
    int n;
    int lev;
    vector<OM> lz;
    virtual OM h(OM, OM) = 0;
    const OM u0;

    DualSegmentTree(OM u0) : u0(u0) {}

    void build(int _n) { init(_n); }

    // 半開区間 [a, b) に対する更新クエリ (a, b: 0-indexed)
    void update(int a, int b, OM x) {
        thrust(a += n);
        thrust(b += n - 1);
		for (int l = a, r = b + 1; l < r; l >>= 1, r >>= 1) {
            if (l & 1) lz[l] = h(lz[l], x), l++;
            if (r & 1) --r, lz[r] = h(lz[r], x);
		}
    }

    // k番目の要素に対する取得クエリ (k: 0-indexed)
    OM query(int k) {
        thrust(k += n);
        return lz[k];
    }

    void dump(int time = -1) {
        if (~time) cerr << "time = " << time << endl;
        for (int i = 0; i <= lev; ++i) {
            int m = 1 << i;
            for (int j = 0; j < m; ++j) {
                cerr << "  " << lz[j + m];
            }
            cerr << endl;
        }
        cerr << endl;
    }
};
template <class OM = int> using DST = DualSegmentTree<OM>;


// Range Update Query (RUQ)
template <class OM = int>
struct RUQ : public DualSegmentTree<OM> {
    using DualSegmentTree<OM>::DualSegmentTree;
    RUQ() : RUQ(numeric_limits<OM>::max()) {}
    OM h(OM a, OM b) override { return b; }
};

// Range Add Query (RAQ)
template <class OM = int>
struct RAQ : DualSegmentTree<OM> {
    using DualSegmentTree<OM>::DualSegmentTree;
    RAQ() : RAQ(0) {}
    OM h(OM a, OM b) override { return a + b; }
};

int N, P;
string S;

// Range Multiple Query
template <class OM = int>
struct RMQ : DualSegmentTree<OM> {
    using DualSegmentTree<OM>::DualSegmentTree;
    RMQ() : RMQ(1) {}
    OM h(OM a, OM b) override { return a * b % P; }
};

void _main() {
    cin >> N >> P >> S;
    if (P == 2 || P == 5) {
        int ans = 0;
        REP (i, N) {
            if ((S[i] - '0') % P == 0) {
                ans += i + 1;
            }
        }
        cout << ans << endl;
        return;
    }
    RMQ<int> rmq;
    rmq.build(N);
    vector<int> a(N);
    a[0] = (S[0] - '0') % P;
    FOR (i, 1, N) a[i] = (a[i - 1] * 10 + (S[i] - '0')) % P;
    REP (i, N) rmq.update(i, i + 1, a[i]);
    REP (i, N) rmq.update(0, i + 1, 10);
    vector<int> b(N);
    REP (i, N) b[i] = rmq.query(i);
    int ans = 0;
    map<int, int> mp;
    REP (i, N) {
        ans += mp[b[i]];
        mp[b[i]]++;
        if (b[i] == 0) ans++;
    }
    cout << ans << endl;
}

signed main(signed argc, char **argv) {
    if (argc > 1) {
        if (strchr(argv[1], 'i')) freopen("input.txt", "r", stdin);
        if (strchr(argv[1], 'o')) freopen("output.txt", "w", stdout);
    }
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << fixed << setprecision(10);
    _main();
    return 0;
}

Measured memory_bytes: 8340