Description

 1  2  3  4 516 17 18 19 615 24 25 20 714 23 22 21 813 12 11 10 9

Input

Output

Sample Input

5 5
1 2 3 4 5
16 17 18 19 6
15 24 25 20 7
14 23 22 21 8
13 12 11 10 9

Sample Output

25

#include<iostream>
#include<cstdio>
#include<cstring>using namespace std;int map[110][110];
int dp[110][110];   //这个位置能走的最远距离
int maxx,p;int mark[4][2] = {{0,1},{0,-1},{-1,0},{1,0}};void Dfs(int x, int y, int t)
{int i,j,q,now;if(map[x][y] == -1)  //到边缘退出{return ;}if(dp[x][y]!=0)  //这条路经已经求出最长，则接下来的不用再搜了，剪枝{t = t+dp[x][y];if(t > p){p = t;}return ;}t = t+1;  //当前这个位置没有求过最优解并且没有离开边界if(t > p){p = t;}for(q = 0; q < 4; q++){i = x+mark[q][0];j = y+mark[q][1];if(map[i][j] < map[x][y]){now = t;Dfs(i,j,now);}}return ;
}int main()
{int r,c,t,i,j;while(scanf("%d%d",&r,&c)!=EOF){maxx = 0;memset(map,-1,sizeof(map));memset(dp,0,sizeof(dp));for(i = 1; i <= r; i++){for(j = 1; j <= c; j++){scanf("%d",&map[i][j]);}}for(i = 1; i <= r; i++){for(j = 1; j <= c; j++){t = 0;       //清空p = 0;Dfs(i,j,t);dp[i][j] = p;   //记录这个位置的最远距离if(p > maxx){maxx = p;}printf("%d ",dp[i][j]);}printf("\n");}printf("%d\n",maxx);}return 0;
}

花姐AC代码：

#include<stdio.h>
int n,m;
int map[100][100];
int lon[100][100];
int dir[4][2]= {1,0,0,1,-1,0,0,-1};
bool inmap(int x,int y)
{if(x>=0&&x<n&&y>=0&&y<m)return true;elsereturn false;
}
int dfs(int x,int y)
{int nx,ny,i;int max1=1;if(lon[x][y]>1)return lon[x][y];for(i=0; i<4; i++){nx=x+dir[i][0];ny=y+dir[i][1];if(inmap(nx,ny)&&map[x][y]>map[nx][ny]){lon[x][y]=dfs(nx,ny)+1;if(lon[x][y]>max1)max1=lon[x][y];}}lon[x][y]=max1;return max1;
}
int main()
{int i,j;int longest;scanf("%d%d",&n,&m);longest=1;for(i=0; i<n; i++)for(j=0; j<m; j++){scanf("%d",&map[i][j]);lon[i][j]=1;}for(i=0; i<n; i++){for(j=0; j<m; j++){int t=dfs(i,j);longest=longest>t?longest:t;}}for(i=0; i<n; i++){for(j=0; j<m; j++){printf("%d ",lon[i][j]);}printf("\n");}printf("%d\n",longest);return 0;
}

随机产生输入数据程序(in)代码：

#include <cstdio>
#include <ctime>
#include <time.h>
#include <cstdlib>
using namespace std;
double radom()         //生成[0,1]之间的均匀随机数
{return (double)rand()/RAND_MAX;
}
//int random(int m)
//{
//    return (int)(random()*(m-1)+0.5);
//}
int main()
{int n,m, i, j, x;srand(time(NULL));    //散播随机种子（头文件需要time.h和stdlib.h）n = rand()%100 +1;    //产生1到100的随机数并赋值给nm = rand()%100 +1;
//    freopen("in.txt","r",stdout);printf("%d %d\n",n,m);
//    scanf("%d",&n);for(i=0; i<n; i++){for(j=0; j<m; j++){x = rand()%100000;printf("%d ",x);}printf("\n");}return 0;
}

windows下批处理对比文件指令（用txt写完后改为bat批处理格式）：