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#include <algorithm>
#include <iostream>
#include <utility>
using namespace std;

#include "message.h"

namespace {
  struct Cost {
    int physical;
    int emotional;

    constexpr Cost(int p=0, int e=0):
      physical{p}, emotional{e}
    {
    }
  };

  constexpr Cost operator+(Cost const& a, Cost const& b)
  {
    return Cost{a.physical + b.physical, a.emotional + b.emotional};
  }

  Cost& operator+=(Cost& a, Cost const& b)
  {
    return a = a + b;
  }

  constexpr bool operator==(Cost const& a, Cost const& b)
  {
    return a.physical == b.physical && a.emotional == b.emotional;
  }

  constexpr bool operator!=(Cost const& a, Cost const& b)
  {
    return !(a == b);
  }

  constexpr bool operator<(Cost const& a, Cost const& b)
  {
    return a.physical != b.physical ? a.physical < b.physical : a.emotional < b.emotional;
  }

  constexpr bool operator>(Cost const& a, Cost const& b)
  {
    return b < a;
  }

  constexpr bool operator<=(Cost const& a, Cost const& b)
  {
    return !(a > b);
  }

  constexpr bool operator>=(Cost const& a, Cost const& b)
  {
    return !(a < b);
  }

  template <typename OS>
  OS& operator<<(OS& s, Cost const& c)
  {
    return s << c.physical << ' ' << c.emotional;
  }

  void put(int target, Cost const& c)
  {
    PutInt(target, c.physical);
    PutInt(target, c.emotional);
  }

  Cost get(int source)
  {
    int p = GetInt(source);
    int e = GetInt(source);
    return {p, e};
  }

  void solve(string const& a, string const& b, int l, int r, int split)
  {
    int const k = NumberOfNodes();
    int const id = MyNodeId();

    int const n = a.size();
    vector<Cost> prev(n+1);
    int rc = 0;
    if (id == 0) {
      rc = n;
      iota(prev.begin(), prev.end(), 0);
    }
    int sc = 0;
    if (id == k-1) sc = n;

    vector<Cost> next(n+1);

    vector<Cost> tabc(r-l+1);

    iota(tabc.begin(), tabc.end(), l-1);
    vector<Cost> tabn(r-l+1);
    for (int i = 1; i <= n; ++i) {
      if (i > rc) {
        int const q = min(rc + 1 + split, n);
        Receive(id-1);
        while (rc < q) {
          ++rc;
          prev[rc] = get(id-1);
        }
      }
      char const x = a[i-1];
      tabn.front() = prev[i];
      for (int j = l; j < r; ++j) {
        char const y = b[j-1];
        int const q = j-l+1;
        tabn[q] = min(tabc[q] + 1, tabn[q-1] + 1);
        if (x == y) {
          tabn[q] = min(tabn[q], tabc[q-1]);
        } else if (x > y) {
          tabn[q] = min(tabn[q], tabc[q-1] + 1);
        } else {
          tabn[q] = min(tabn[q], tabc[q-1] + Cost{1,1});
        }
      }
      swap(tabn, tabc);
      next[i] = tabc.back();
      if (id < k-1 && (i-sc > split || i == n)) {
        for (int q = sc+1; q <= i; ++q) {
          put(id+1, next[q]);
        }
        Send(id+1);
        sc = i;
      }
    }

    if (id == k-1) {
      cout << next.back() << endl;
    }
  }
}


int main()
{
  int const k = NumberOfNodes();
  int const id = MyNodeId();

  int n, m;
  cin >> n >> m;
  string a, b;
  cin >> a >> b;

  int const split = 1000;

  int const l = (id + 0LL) * m / k + 1;
  int const r = (id + 1LL) * m / k + 1;

  solve(a, b, l, r, split);

  return 0;
}