Solution C

#include "stdio.h"
int a[101][101],b[101][101],d[101][101];
int m,n;
int max;
int F(int i,int j)
{
	if(b[i][j])
		return d[i][j];
	if(i>1&&a[i][j]>a[i-1][j])
		d[i][j]=d[i][j]>F(i-1,j)+1?d[i][j]:F(i-1,j)+1;
	if(i<m&&a[i][j]>a[i+1][j])
		d[i][j]=d[i][j]>F(i+1,j)+1?d[i][j]:F(i+1,j)+1;
	if(j>1&&a[i][j]>a[i][j-1])
		d[i][j]=d[i][j]>F(i,j-1)+1?d[i][j]:F(i,j-1)+1;
	if(j<m&&a[i][j]>a[i][j+1])
		d[i][j]=d[i][j]>F(i,j+1)+1?d[i][j]:F(i,j+1)+1;
	b[i][j]=1;
	return d[i][j];
}
int main()
{
	int i,j;
	scanf("%d%d",&m,&n);
	for(i=1;i<=m;i++)
		for(j=1;j<=n;j++)
		{
			scanf("%d",&a[i][j]);
			b[i][j]=0;
			d[i][j]=1;
		}
		max=1;
		for(i=1;i<=m;i++)
			for(j=1;j<=n;j++)
				if(max<F(i,j))
					max=F(i,j);
				printf("%d\n",max);
}

Solution C++

#include<iostream>
#include<algorithm>
#include<cstring>
using namespace std;
const int dx[4]={-1, 1, 0, 0},
          dy[4]={ 0, 0,-1, 1};
struct node{ int x,y,h;};
node a[10005];
int map[105][105],len[105][105]={0};
bool comp(const node &x,const node &y)
{   return x.h<y.h;  }
void dp(int i)
{
    int x0,y0,x1,y1;
    x0=a[i].x;  y0=a[i].y;
    for (int j=0;j<4;j++)
    {
        x1=x0+dx[j];
        y1=y0+dy[j];
        if (map[x1][y1]<map[x0][y0]&&len[x1][y1]>len[x0][y0])
            len[x0][y0]=len[x1][y1];
    }
    len[x0][y0]++;
}
int main()
{
//    ifstream cin("ski.in");
//    ofstream cout("ski.out");
    int row,col;
    while (cin>>row>>col)
    {
        int k=0;
        for (int i=1;i<=row;i++)
            for (int j=1;j<=col;j++)
            {
                cin>>map[i][j];
                a[k].x=i;  a[k].y=j;  a[k++].h=map[i][j];
            }
        sort(a,a+k,comp);
        memset(len,0,sizeof(len));
        for (int i=0;i<k;i++) dp(i);        
        int ans(0);
        for (int i=1;i<=row;i++)
            for (int j=1;j<=col;j++)
                if (len[i][j]>ans) ans=len[i][j];
        cout<<ans<<endl;
    }
   // system("pause");
    return 0;
}

Solution Java

import java.util.Scanner;


public class Main {
	static final int M = 105;
	static int[][] matrix = new int[M][M];
	static int[][] dp = new int[M][M];
	static int r,c;
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNextInt()){
			r = in.nextInt();
			c = in.nextInt();
			for(int i=0;i<r;i++){
				for(int j=0;j<c;j++){
					matrix[i][j] = in.nextInt();
				}
			}
			for(int i=0;i<r;i++){
				for(int j=0;j<c;j++){
					maxLength(i,j);
				}
			}
			int max = -1;
			for(int i=0;i<r;i++){
				for(int j=0;j<c;j++){
					if(max<dp[i][j])
						max = dp[i][j];
				}
			}
			System.out.println(max);
		}
	}

	public static int max(int a, int b, int c, int d) {
		int m1 = a > b ? a : b;
		int m2 = c > d ? c : d;
		return (m1 > m2 ? m1 : m2);
	}

	public static int maxLength(int i, int j) {
		if (dp[i][j] > 0)
			return dp[i][j];
		int a = 0, b = 0, c = 0, d = 0;
		if (i - 1 >= 0 && matrix[i][j] > matrix[i - 1][j])
			a = matrix[i - 1][j];
		if (i + 1 < r && matrix[i][j] > matrix[i + 1][j])
			b = matrix[i + 1][j];
		if (j - 1 >= 0 && matrix[i][j] > matrix[i][j - 1])
			c = matrix[i][j - 1];
		if (j + 1 < c && matrix[i][j] > matrix[i][j + 1])
			d = matrix[i][j + 1];
		dp[i][j] = max(a, b, c, d) + 1;
		return dp[i][j];
	}
}