#include<bits/stdc++.h>

using namespace std;
const int MOD = 1000696969;

int powmod(int a, int b, int m) {
    int res = 1;
    while (b) {
        if (b & 1) res = (1ll * res * a) % m;
        a = (1ll * a * a) % m;
        b >>= 1;
    }
    return res;
}
struct mod {
    const static int k = 2;
    const static int p[k];
    int x[k];
    mod() {
        memset(x, 0, sizeof x);
    }
    mod(int val) {
        for (int i = 0; i < k; i++) x[i] = val % p[i];
    }
    mod operator+=(const mod& a) {
        for (int i = 0; i < k; i++) {
            x[i] = (0ll + x[i] + a.x[i]) % p[i];
            if (x[i] < 0)
                x[i] += p[i];
        }
        return *this;
    }
    mod operator-=(const mod& a) {
        for (int i = 0; i < k; i++) {
            x[i] = (0ll + x[i] - a.x[i] + p[i]) % p[i];
        }
        return *this;
    }
    mod operator*=(const mod& a) {
        for (int i = 0; i < k; i++) {
            x[i] = (1ll * x[i] * a.x[i]) % p[i];
        }
        return *this;
    }
    mod operator/=(const mod& a) {
        mod inv = mod(a).inverse();
        return *this *= inv;
    }
    mod inverse() const {
        int inv[k];
        for (int i = 0; i < k; i++) {
            inv[i] = powmod(x[i], p[i] - 2, p[i]);
        }
        mod result;
        for (int i = 0; i < k; i++) {
            result.x[i] = inv[i];
        }
        return result;
    }
    bool operator==(const mod& other) const {
        for (int i = 0; i < k; i++) {
            if (x[i] != other.x[i]) {
                return false;
            }
        }
        return true;
    }
    bool operator!=(const mod& other) const {
        return !(*this == other);
    }
};
const int mod::p[mod::k] = {1000000007, 1000000009};

mod operator+(mod a, const mod& b) { return a += b; }
mod operator-(mod a, const mod& b) { return a -= b; }
mod operator*(mod a, const mod& b) { return a *= b; }
mod operator/(mod a, const mod& b) { return a /= b; }

vector<int> get_digits(string s) {
    vector<int> digits;
    for (char c : s) digits.push_back(c - '0');
    reverse(digits.begin(), digits.end());
    return digits;
}

mod Hash(vector<int> &digits) {
    mod res = mod();
    for (int i = digits.size() - 1; i >= 0; i--) {
        res = res * mod(10) + mod(digits[i]);
    }
    return res;
}
void add(vector<mod> &a, vector<int> &digits, int k) {
    int n = digits.size();
    vector<int> num(k);
    for (int i = 0; i < n; i++) {
        num[i%k] += digits[i];
    }
    for (int i = 0; i < num.size(); i++) {
        if (num[i] < 10) continue;
        if (i + 1 == num.size()) num.push_back(0);
        num[i + 1] += num[i] / 10;
        num[i] %= 10;
    }
    if (num.size() == k) {
        bool flag = 1;
        for (int i = 0; i < k; i++) if (num[i] != 9) flag = 0;
        if (flag) 
            for (int i = 0; i < k; i++) num[i] = 0;
        a.push_back(Hash(num));
    } else {
        add(a, num, k);
    }
}
map<mod, int> cnt;

int threesum(vector<mod> &a, mod s) {
    int n = a.size();
    int ans = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) if (i != j) {
            mod rem = s - (a[i] + a[j]);
            if (rem == a[i]) ans--;
            if (rem == a[j]) ans--;
            ans += cnt[rem];
        }
    }
    ans /= 6;
    for (int i = 0; i < n; i++) {
        mod rem = s - (a[i] + a[i]);
        ans += cnt[rem];
    }
    return ans;
}
void Solve() {
    int n, k; cin >> n >> k;
    vector<mod> a;
    for (int i = 0; i < n; i++) {
        string s; cin >> s;
        vector<int> digits = get_digits(s);
        add(a, digits, k);
    }
    for (int i = 0; i < n; i++) cnt[a[i]]++;
    int ans = 0;
    ans += threesum(a, 0);
    vector<int> d;
    for (int i = 0; i < k; i++) d.push_back(9);
    mod h = Hash(d);
    ans += threesum(a, h);
    d.clear();
    d.push_back(8);
    for (int i = 0; i < k - 1; i++) d.push_back(9);
    d.push_back(1);
    h = Hash(d);
    ans += threesum(a, h);
    cout << ans << '\n';
}
int main () {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int t = 1; //cin >> t;
    while (t--) Solve();
}

In file included from /usr/include/c++/13/string:49,
                 from /usr/include/c++/13/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:52,
                 from answer.code:1:
/usr/include/c++/13/bits/stl_function.h: In instantiation of ‘constexpr bool std::less<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = mod]’:
/usr/include/c++/13/bits/stl_map.h:511:32:   required from ‘std::map<_Key, _Tp, _Compare, _Alloc>::mapped_type& std::map<_Key, _Tp, _Compare, _Alloc>::operator[](const key_type&) [with _Key = mod; _Tp = int; _Compare = std::less<mod>; _Alloc = std::allocator<std::pair<const mod, int> >; mapped_type = int; key_type = mod]’
answer.code:125:27:   required from here
/usr/include/c++/13/bits/stl_function.h:408:20: error: no match for ‘operator<’ (operand types are ‘const mod’ and ‘const mod’)
  408 |       { return __x < __y; }
      |                ~~~~^~~~~
In file included from /usr/include/c++/13/bits/stl_algobase.h:64,
                 from /usr/include/c++/13/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:51:
/usr/include/c++/13/bits/stl_pair.h:835:5: note: candidate: ‘template<class _T1, class _T2> constexpr bool std::operator<(const pair<_T1, _T2>&, const pair<_T1, _T2>&)’
  835 |     operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/13/bits/stl_pair.h:835:5: note:   template argument deduction/substitution failed:
/usr/include/c++/13/bits/stl_function.h:408:20: note:   ‘const mod’ is not derived from ‘const std::pair<_T1, _T2>’
  408 |       { return __x < __y; }
      |                ~~~~^~~~~
In file included from /usr/include/c++/13/bits/stl_algobase.h:67:
/usr/include/c++/13/bits/stl_iterator.h:455:5: note: candidate: ‘template<class _Iterator> bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)’
  455 |     operator<(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/13/bits/stl_iterator.h:455:5: note:   template argument deduction/substitution failed:
/usr/include/c++/13/bits/stl_function.h:408:20: note:   ‘const mod’ is not derived from ‘const std::reverse_iterator<_Iterator>’
  408 |       { return __x < __y; }
      |                ~~~~^~~~~
/usr/include/c++/13/bits/stl_iterator.h:500:5: note: candidate: ‘template<class _IteratorL, class _IteratorR> bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)’
  500 |     operator<(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/13/bits/stl_iterator.h:500:5: note:   template argument deduction/substitution failed:
/usr/include/c++/13/bits/stl_function.h:408:20: note:   ‘const mod’ is not derived from ‘const std::reverse_iterator<_Iterator>’
  408 |       { return __x < __y; }
      |                ~~~~^~~~~
/usr/include/c++/13/bits/stl_iterator.h:1705:5: note: candidate: ‘template<class _IteratorL, class _IteratorR> bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)’
 1705 |     operator<(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/13/bits/stl_iterator.h:1705:5: note:   template argument deduction/substitution failed:
/usr/include/c++/13/bits/stl_function.h:408:20: note:   ‘const mod’ is not derived from ‘const std::move_iterator<_IteratorL>’
  408 |       { return __x < __y; }
      |                ~~~~^~~~~
/usr/include/c++/13/bits/stl_iterator.h:1770:5: note: candidate: ‘template<class _Iterator> bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)’
 1770 |     operator<(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/13/bits/stl_iterator.h:1770:5: note:   template argument deduction/substitution failed:
/usr/include/c++/13/bits/stl_function.h:408:20: note:   ‘const mod’ is not derived from ‘const std::move_iterator<_IteratorL>’
  408 |       { return __x < __y; }
      |                ~~~~^~~~~