Problem:
Score : 500 points

Problem Statement

We have a grid with H horizontal rows and W vertical columns. Let (i,j) denote the square at the i-th row from the top and the j-th column from the left.

The square (i, j) has two numbers A_{ij} and B_{ij} written on it.

First, for each square, Takahashi paints one of the written numbers red and the other blue.

Then, he travels from the square (1, 1) to the square (H, W). In one move, he can move from a square (i, j) to the square (i+1, j) or the square (i, j+1). He must not leave the grid.

Let the unbalancedness be the absolute difference of the sum of red numbers and the sum of blue numbers written on the squares along Takahashi's path, including the squares (1, 1) and (H, W).

Takahashi wants to make the unbalancedness as small as possible by appropriately painting the grid and traveling on it.

Find the minimum unbalancedness possible.

Constraints

2 \leq H \leq 80

2 \leq W \leq 80

0 \leq A_{ij} \leq 80

0 \leq B_{ij} \leq 80

All values in input are integers.

Input

Input is given from Standard Input in the following format:

H W
A_{11} A_{12} \ldots A_{1W}
:
A_{H1} A_{H2} \ldots A_{HW}
B_{11} B_{12} \ldots B_{1W}
:
B_{H1} B_{H2} \ldots B_{HW}

Output

Print the minimum unbalancedness possible.

Sample Input 1

2 2
1 2
3 4
3 4
2 1

Sample Output 1

0

By painting the grid and traveling on it as shown in the figure below, the sum of red numbers and the sum of blue numbers are 3+3+1=7 and 1+2+4=7, respectively, for the unbalancedness of 0.

Sample Input 2

2 3
1 10 80
80 10 1
1 2 3
4 5 6

Sample Output 2

2

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Linq;
using System.Collections.Generic;

namespace Contest
{
    class Program
    {
        static void Main(string[] args)
        {
            ABC147.E();
        }

        class ABC147
        {
            public static void A()
            {
                Console.WriteLine(Read.Int() + Read.Int() + Read.Int() >= 22 ? "bust" : "win");
            }
            public static void B()
            {
                var S = Read.Str();
                int count = 0;
                for(int i = 0; i < S.Length / 2; ++i)
                {
                    if (S[i] != S[S.Length - 1 - i]) { count++; }
                }
                Console.WriteLine(count);
            }
            public static void C()
            {
                var N = Read.Int();
                List<Tuple<int, int>[]> XYs = new List<Tuple<int, int>[]>();
                for(int i = 0; i < N; ++i)
                {
                    var A = Read.Int();
                    XYs.Add(Read.TupleInt(A));
                }
                int max = 0;
                for(int i = 0; i < (1 << N); ++i)
                {
                    int count = 0;
                    bool ok = true;
                    for(int j = 0; j < N; ++j)
                    {
                        if ((i & (1 << j)) > 0)
                        {
                            count++;
                            foreach(var XY in XYs[j])
                            {
                                var x = XY.Item1 - 1;
                                var y = XY.Item2;
                                if((i & (1 << x)) > 0 != (y == 1))
                                {
                                    ok = false;
                                }
                            }
                        }
                    }
                    if (ok) { max = Math.Max(max, count); }
                }
                Console.WriteLine(max);
            }
            public static void D()
            {
                var N = Read.Int();
                var A = Read.LongN();
                var count1 = new long[61];
                foreach(var a in A)
                {
                    for(int i = 0; i < count1.Length; ++i)
                    {
                        if((a & (1L << i)) > 0) { count1[i]++; }
                    }
                }
                long sum = 0;
                long pow2 = 1;
                for(int i = 0; i < count1.Length; ++i)
                {
                    sum += (((count1[i] * (N - count1[i])) % Util.P) * pow2) % Util.P;
                    pow2 = (pow2 * 2) % Util.P;
                }
                Console.WriteLine(sum % Util.P);
            }
            public static void E()
            {
                var H = Read.Int();
                var W = Read.Int();
                var A = Read.LongMatrix(H, W);
                var B = Read.LongMatrix(H, W);
                var dp = new System.Collections.BitArray[H, W];
                int maxV = 6500;
                for(int i = 0; i < H; ++i)
                {
                    for(int j = 0; j < W; ++j)
                    {
                        var bit = new System.Collections.BitArray(maxV);
                        dp[i, j] = bit; 
                        var diff = (int)Math.Abs(A[i, j] - B[i, j]);
                        if (i == 0 && j == 0) { bit[diff] = true; }
                        else
                        {
                            System.Collections.BitArray prev;
                            if (i > 0 && j > 0)
                            {
                                prev = dp[i - 1, j].Or(dp[i, j - 1]);
                            }
                            else
                            {
                                prev = i > 0 ? dp[i - 1, j] : dp[i, j - 1];
                            }
                            for (int k = 0; k < maxV; ++k)
                            {
                                if (k >= diff) { bit[k] |= prev[k - diff]; } else { bit[k] |= prev[diff - k]; }
                                if (k < maxV - diff) { bit[k] |= prev[k + diff]; }
                            }
                        }
                    }
                }
                for (int i = 0; i < maxV; ++i)
                {
                    if (dp[H - 1, W - 1][i])
                    {
                        Console.WriteLine(i); break;
                    }
                }
            }
            public static void F()
            {

            }
        }
        class Util
        {
            public static readonly long P = 1000000007;

            public static long GCD(long a, long b)
            {
                while (b > 0)
                {
                    var c = a % b;
                    a = b;
                    b = c;
                }
                return a;
            }

        }
        class Graph
        {
        }

        static class Read
        {
            static Queue<string> queue = new Queue<string>();
            static void Enqueue() { var ss = Console.ReadLine().Split(' '); foreach (var s in ss) { queue.Enqueue(s); } }
            public static int Int() { if (queue.Count == 0) { Enqueue(); } return Convert.ToInt32(queue.Dequeue()); }
            public static long Long() { if (queue.Count == 0) { Enqueue(); } return Convert.ToInt64(queue.Dequeue()); }
            public static string Str() { if (queue.Count == 0) { Enqueue(); } return queue.Dequeue(); }
            public static int[] IntN() { return Console.ReadLine().Split(' ').Select(s => Convert.ToInt32(s)).ToArray(); }
            public static long[] LongN() { return Console.ReadLine().Split(' ').Select(s => Convert.ToInt64(s)).ToArray(); }
            public static string[] StrN() { return Console.ReadLine().Split(' '); }
            public static Tuple<int, int>[] TupleInt(int n) { List<Tuple<int, int>> list = new List<Tuple<int, int>>(); for (int i = 0; i < n; ++i) { var ab = Read.IntN(); list.Add(new Tuple<int, int>(ab[0], ab[1])); } return list.ToArray(); }
            public static Tuple<long, long>[] TupleLong(int n) { List<Tuple<long, long>> list = new List<Tuple<long, long>>(); for (int i = 0; i < n; ++i) { var ab = Read.LongN(); list.Add(new Tuple<long, long>(ab[0], ab[1])); } return list.ToArray(); }
            public static Tuple<string, string>[] TupleStr(int n) { List<Tuple<string, string>> list = new List<Tuple<string, string>>(); for (int i = 0; i < n; ++i) { var ab = Read.StrN(); list.Add(new Tuple<string, string>(ab[0], ab[1])); } return list.ToArray(); }
            public static Tuple<double, double>[] TupleDouble(int n) { List<Tuple<double, double>> list = new List<Tuple<double, double>>(); for (int i = 0; i < n; ++i) { var ab = Read.LongN(); list.Add(new Tuple<double, double>(ab[0], ab[1])); } return list.ToArray(); }
            public static long[,] LongMatrix(int r, int c)
            {
                var mat = new long[r, c];
                for (int i = 0; i < r; ++i)
                {
                    var x = Read.LongN();
                    for (int j = 0; j < c; ++j)
                    {
                        mat[i, j] = x[j];
                    }
                }
                return mat;
            }
            public static Dictionary<int, HashSet<int>> AdjacencyList(int N, int M)
            {
                Dictionary<int, HashSet<int>> dict = new Dictionary<int, HashSet<int>>();
                for (int i = 0; i <= N; ++i)
                {
                    dict.Add(i, new HashSet<int>());
                }
                for (int i = 0; i < M; ++i)
                {
                    var ab = Read.IntN();
                    dict[ab[0]].Add(ab[1]);
                    dict[ab[1]].Add(ab[0]);
                }
                return dict;
            }
            public static Dictionary<int, Dictionary<int, long>> AdjacencyListWithWeight(int N, int M)
            {
                Dictionary<int, Dictionary<int, long>> dict = new Dictionary<int, Dictionary<int, long>>();
                for (int i = 0; i <= N; ++i)
                {
                    dict.Add(i, new Dictionary<int, long>());
                }
                for (int i = 0; i < M; ++i)
                {
                    var ab = Read.IntN();
                    dict[ab[0]].Add(ab[1], ab[2]);
                    dict[ab[1]].Add(ab[0], ab[2]);
                }
                return dict;
            }
        }
    }
}