poj 1088 滑雪问题

 滑雪问题 

 

import java.util.Scanner;
public class Main{
	static int a[][],r,c;
    public static void main(String [] args){
        Scanner input=new Scanner(System.in);
        
        while(input.hasNext()){
        	r=input.nextInt();
        	c=input.nextInt();
        	a=new int[r][c];
        	int b[][]=new int[r][c];
        	int min=Integer.MIN_VALUE;
        	for(int i=0;i<r;i++){
        		for(int j=0;j<c;j++){
        			a[i][j]=input.nextInt();
        		}
        	}
        	int sum=1;
        	for(int i=0;i<r;i++){
        		for(int j=0;j<c;j++){
        			b[i][j]=sou(i,j,sum,b);
        			if(b[i][j]>min)
        				min=b[i][j];
        		}
        	}
        	System.out.println(min);
        }
    }
	private static int sou(int i, int j, int sum,int b[][]) {
		int e=1;
		if(j+1<c&&a[i][j]>a[i][j+1]){
			if(b[i][j+1]>0){
				//return sum+b[i][j+1];
				int num=sum+b[i][j+1];
				if(num>e)
					e=num;
			}
			else{
				//return sum+sou(i,j+1,sum,b);
				int num=sum+sou(i,j+1,sum,b);
				if(num>e)
					e=num;
			}
		}
		if(i+1<r&&a[i][j]>a[i+1][j]){
			if(b[i+1][j]>0){
				//return sum+b[i+1][j];
				int num=sum+b[i+1][j];
				if(num>e)
					e=num;
			}
			else{
				//return sum+sou(i+1,j,sum,b);
				int num=sum+sou(i+1,j,sum,b);
				if(num>e)
					e=num;
			}
		}
		if(j-1>=0&&a[i][j]>a[i][j-1]){
			if(b[i][j-1]>0){
				//return sum+b[i][j-1];
				int num=sum+b[i][j-1];
				if(num>e)
					e=num;
			}
			else{
				//return sum+sou(i,j-1,sum,b);
				int num=sum+sou(i,j-1,sum,b);
				if(num>e)
					e=num;
			}
		}
		if(i-1>=0&&a[i][j]>a[i-1][j]){
			if(b[i-1][j]>0){
				//return sum+b[i-1][j];
				int num=sum+b[i-1][j];
				if(num>e)
					e=num;
			}
			else{
				//return sum+sou(i-1,j,sum,b);
				int num=sum+sou(i-1,j,sum,b);
				if(num>e)
					e=num;
			}
		}
		
		return e;
	}
}