using System;
using System.Linq;
using System.Collections.Generic;
using Debug = System.Diagnostics.Debug;
using StringBuilder = System.Text.StringBuilder;
using System.Numerics;
namespace Program
{
    public class Solver
    {
        public void Solve()
        {
            var n = sc.Integer();
            var hp = (short)sc.Integer();
            var sx = (short)(sc.Integer() - 1);
            var sy = (short)(sc.Integer() - 1);
            var gx = (short)(sc.Integer() - 1);
            var gy = (short)(sc.Integer() - 1);
            var map = Enumerate(n, x => sc.Integer(n));
            var dist = Enumerate(n * n, x => new SegmentTree(n * n));
            ;
            dist[sx + sy * n].Update(0, hp);
            var q = new Queue<State>();
            q.Enqueue(new State((short)(sx + sy * n), 0, hp));
            short[] dx = { 0, 0, 1, -1 };
            short[] dy = { 1, -1, 0, 0 };
            while (q.Any())
            {
                var p = q.Dequeue();
                var py = p.pos / n;
                var px = p.pos % n;
                if (dist[py * n + px][p.dist] > p.hp)
                    continue;
                if (p.dist + 1 >= n * n)
                    continue;
                for (int i = 0; i < 4; i++)
                {
                    short ny = (short)(py + dy[i]);
                    short nx = (short)(px + dx[i]);
                    if (ny < 0 || ny >= n || nx < 0 || nx >= n)
                        continue;
                    var nhp = (short)(p.hp - map[ny][nx]);
                    if (dist[ny * n + nx][0, p.dist + 2] < nhp)
                    {
                        dist[ny * n + nx].Update(p.dist + 1, nhp);
                        q.Enqueue(new State((short)(ny * n + nx), (short)(p.dist + 1), nhp));
                    }
                }

            }
            for (int i = 0; i < n * n; i++)
                if (dist[gy * n + gx][i] > 0)
                {
                    IO.Printer.Out.WriteLine(i);
                    return;
                }
            IO.Printer.Out.WriteLine(-1);
        }

        public IO.StreamScanner sc = new IO.StreamScanner(Console.OpenStandardInput());
        static T[] Enumerate<T>(int n, Func<int, T> f) { var a = new T[n]; for (int i = 0; i < n; ++i) a[i] = f(i); return a; }

    }


}

struct State
{
    public short pos;
    public short dist, hp;
    public State(short p, short d, short v)
        : this()
    {
        pos = p; dist = d; hp = v;

    }
}
#region Ex
namespace Program.IO
{
    using System.IO;
    using System.Text;
    using System.Globalization;
    public class Printer : StreamWriter
    {
        static Printer() { Out = new Printer(Console.OpenStandardOutput()) { AutoFlush = false }; }
        public static Printer Out { get; set; }
        public override IFormatProvider FormatProvider { get { return CultureInfo.InvariantCulture; } }
        public Printer(System.IO.Stream stream) : base(stream, new UTF8Encoding(false, true)) { }
        public Printer(System.IO.Stream stream, Encoding encoding) : base(stream, encoding) { }
        public void Write<T>(string format, IEnumerable<T> source) { base.Write(format, source.OfType<object>().ToArray()); }
        public void WriteLine<T>(string format, IEnumerable<T> source) { base.WriteLine(format, source.OfType<object>().ToArray()); }
    }
    public class StreamScanner
    {
        public StreamScanner(Stream stream) { str = stream; }
        private readonly Stream str;
        private readonly byte[] buf = new byte[1024];
        private int len, ptr;
        public bool isEof = false;
        public bool IsEndOfStream { get { return isEof; } }
        private byte read()
        {
            if (isEof) return 0;
            if (ptr >= len) { ptr = 0; if ((len = str.Read(buf, 0, 1024)) <= 0) { isEof = true; return 0; } }
            return buf[ptr++];
        }
        public char Char() { byte b = 0; do b = read(); while (b < 33 || 126 < b); return (char)b; }

        public string Scan()
        {
            var sb = new StringBuilder();
            for (var b = Char(); b >= 33 && b <= 126; b = (char)read())
                sb.Append(b);
            return sb.ToString();
        }
        public long Long()
        {
            if (isEof) return long.MinValue;
            long ret = 0; byte b = 0; var ng = false;
            do b = read();
            while (b != '-' && (b < '0' || '9' < b));
            if (b == '-') { ng = true; b = read(); }
            for (; true; b = read())
            {
                if (b < '0' || '9' < b)
                    return ng ? -ret : ret;
                else ret = ret * 10 + b - '0';
            }
        }
        public int Integer() { return (isEof) ? int.MinValue : (int)Long(); }
        public double Double() { return double.Parse(Scan(), CultureInfo.InvariantCulture); }
        private T[] enumerate<T>(int n, Func<T> f)
        {
            var a = new T[n];
            for (int i = 0; i < n; ++i) a[i] = f();
            return a;
        }

        public char[] Char(int n) { return enumerate(n, Char); }
        public string[] Scan(int n) { return enumerate(n, Scan); }
        public double[] Double(int n) { return enumerate(n, Double); }
        public int[] Integer(int n) { return enumerate(n, Integer); }
        public long[] Long(int n) { return enumerate(n, Long); }
    }
}
static class Ex
{
    static public string AsString(this IEnumerable<char> ie) { return new string(System.Linq.Enumerable.ToArray(ie)); }
    static public string AsJoinedString<T>(this IEnumerable<T> ie, string st = " ") { return string.Join(st, ie); }
    static public void Main()
    {
        var solver = new Program.Solver();
        solver.Solve();
        Program.IO.Printer.Out.Flush();
    }
}
#endregion

#region SegTree
[System.Diagnostics.DebuggerDisplay("Data={ToString()}")]
public class SegmentTree
{
    const short Min = 0;
    int n;
    short[] data;
    public SegmentTree(int size)
    {
        n = 1;
        while (n < size)
            n <<= 1;
        data = new short[n << 1];
        //for (int i = 0; i < data.Length; i++)
        //  data[i] = Min;
    }

    // turn kth index value into v
    public void Update(int k, short v)
    {
        k += n;
        data[k] = v;
        k >>= 1;
        while (k > 0)
        {
            data[k] = Math.Max(data[k << 1], data[(k << 1) + 1]);
            k >>= 1;
        }

    }
    public short Query(int a, int b) { return Query(a, b, 1, 0, n); }
    private short Query(int a, int b, int k, int l, int r)
    {
        if (r <= a || b <= l)
            return Min;
        if (a <= l && r <= b)
            return data[k];
        else
        {
            var vl = Query(a, b, k << 1, l, (l + r) >> 1);
            var vr = Query(a, b, (k << 1) + 1, (l + r) >> 1, r);
            return Math.Max(vl, vr);
        }
    }


    ///<summary>Data[i]</summary>>
    public int this[int i] { get { return data[i + n]; } }
    ///<summary>Minimum[a,b)</summary>>
    public int this[int l, int r] { get { return Query(l, r, 1, 0, n); } }
    public override string ToString()
    {
        return string.Join(",", Enumerable.Range(0, n).Select(i => this[i]).Where(v => v != Min));
    }
    public string Visualize()
    {
        var sb = new System.Text.StringBuilder();
        var k = 2;
        var len = n << 1;
        for (int i = 1; i < len; i++)
        {
            if (data[i] != Min) sb.Append(data[i]);
            else sb.Append('-');
            if (i < k - 1) sb.Append(',');
            else if (i < len - 1)
            {
                sb.AppendLine();
                k <<= 1;
            }
        }
        return sb.ToString();
    }
    //*/
}
#endregion