HDU 1069 Monkey and Banana (dp, 最长上升子序列)

题目链接: HDU 1069

题意: 给定n个长方体，每个长方体均有长、宽、高. 将这些长方体（可重复使用）叠起来，满足上面的长方体的长宽>下面的长方体的长宽( 长>长，宽>宽，为严格> )的条件下. 问叠出来的高度最高为多少?

解法: 一个长方体可分为6种类型的长方体( 以不同的边为底边 )， 按照长排序后，进行最长上升子序列求解，即可得到答案.

#include<bits/stdc++.h>
using namespace std;
#define mp make_pair
#define pb push_back
#define fir first
#define sec second
#define repp(i, a, b) for(int i=(b); i>=(a); --i)
#define rep(i,a,b) for (int i=(a); i<=(b); ++i)
#define de(x) cout<< #x << " => " << (x) << endl
#define ms(a, b) memset(a, b, sizeof(a))
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
const int inf = 0x3f3f3f3f;
const double PI=acos(-1);
const double eps=1e-9;
inline void file_put() {
freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);
}
const int maxn = 300;
int n;
struct node{
int w, l , h, area;
}p[maxn];
int len = 0;
void add(int x, int y, int z){
p[len].l = x , p[len].w = y , p[len++].h = z;
p[len].l = y , p[len].w = x, p[len++].h = z;
p[len].l = x , p[len].w = z, p[len++].h = y;
p[len].l = z , p[len].w = x, p[len++].h = y;
p[len].l = y , p[len].w = z, p[len++].h = x;
p[len].l = z , p[len].w = y, p[len++].h = x;
return ;
}
bool cmp(node a, node b){
if(a.l != b.l) return a.l < b.l;
else if(a.w != b.w)return a.w < b.w;
}
int dp[maxn];
int main() {
//  file_put();
int cas=0;
while(~scanf("%d", &n), n){
cout << "Case "<<++cas<<": maximum height = ";
len = 0;
int x, y, z;
ms(dp, 0);
rep(i, 1, n){
scanf("%d %d %d", &x, &y, &z) ;
add(x, y, z);
}
sort(p, p+len, cmp);
rep(i, 0, len-1){
dp[i] = p[i].h;
rep(j, 0, i-1){
if(p[i].l>p[j].l && p[i].w >p[j].w){
if(dp[i] < dp[j] + p[i].h){
dp[i] = dp[j] + p[i].h;
}
}
}
}
int ans = 0;
rep(i, 0, len-1){
ans = max(dp[i], ans);
}
cout << ans<<endl;
}
return 0;
}