UVA 10285 - Longest Run on a Snowboard

这是一道动态规划的dps问题，注意深搜的过程中做到记忆化搜索。

代码如下：

#include<stdio.h>
#include<string.h>
int n, R, C, max, a[105][105], f[105][105];
char name[100];
int dp(int i, int j)
{
    if(f[i][j] != 0) return f[i][j];
    if(i<=R&&i>=1&&j<=C&&j>=1)
    {
        int k, p, q;
        if(a[i][j] > a[i-1][j])
            f[i][j] = dp(i-1, j) + 1;
         if(a[i][j] > a[i+1][j] && f[i][j] < (k=dp(i+1, j)+1))
            f[i][j] = k;
         if(a[i][j] > a[i][j-1] && f[i][j] < (p=dp(i,j-1)+1))
            f[i][j] = p;
         if(a[i][j] > a[i][j+1] && f[i][j] < (q=dp(i,j+1)+1))
            f[i][j] = q; 
       if(f[i][j] == 0) 
             f[i][j] = 1;
    }
    return f[i][j];
}
void input()
{
    while(scanf("%d",&n) == 1)
    while(n --)
    {
        scanf("%s%d%d",name, &R, &C);
        memset(a, 0, sizeof(a));
        memset(f, 0, sizeof(f));
        for(int i = 1; i <= R; i ++)
            for(int j = 1; j <= C; j ++)
                scanf("%d",&a[i][j]);
                max = 0;
        for(int i = 1; i <= R; i ++)
            for(int j = 1; j <= C; j ++)
            {
                int z = dp(i,j);//printf("i=%d j=%d z=%d\n",i, j, z);
                if(z > max) max = z;
            }
        printf("%s: %d\n",name,max);
    }
}
int main()
{
    input();    
    return 0;
}