杭电1069_01背包

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1069

题目大意：给你n块砖， 每块的长， 宽， 高， 可以任意转换方位， 每种砖都有无限个， 用这些砖叠成塔， 上面的长宽要小于在它下面的长宽， 求塔高最高是多少？

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cstdlib>
#include <cmath>
#include <set>
#include <map>
#include <vector>
using namespace std;

struct node
{
    int l, w, h;
}a[100];
int cmp(node a, node b)
{
    if(a.l != b.l)
        return a.l > b.l;
    else
        return a.w > b.w;
}
int main()
{
    int n, x[3], i, j, dp[100], cnt = 0;
    while(~scanf("%d", &n))
    {
        cnt++;
        if(n == 0)
            break;
        for(i = 1; i <= n; i++)
        {
            scanf("%d %d %d", &x[0], &x[1], &x[2]);
            sort(x, x + 3);
            a[i * 3].l = x[2], a[i * 3].w = x[1], a[i * 3].h = x[0];
            a[i * 3 - 1].l = x[1], a[i * 3 - 1].w = x[0], a[i * 3 - 1].h = x[2];
            a[i * 3 - 2].l = x[2], a[i * 3 - 2].w = x[0], a[i * 3 - 2].h = x[1];
        }
        sort(a + 1, a + n * 3 + 1, cmp);
        memset(dp, 0, sizeof(dp));
        int sum = 0;
        for(i = 1; i <= n * 3; i++)
        {
            int t = 0;
            for(j = 1; j <= i; j++)
            {
                if(a[i].l < a[j].l && a[i].w < a[j].w && t < dp[j])
                    t = dp[j];
            }
            dp[i] = t + a[i].h;
            if(dp[i] > sum)
                sum = dp[i];
        }
        printf("Case %d: maximum height = %d
", cnt, sum);
    }
    return 0;
}