Space Elevator
| Time Limit: 1000MS | Memory Limit: 65536K | |
| Total Submissions:14013 | Accepted: 6697 |
Description
The cows are going to space! They plan to achieve orbit by building a sort of space elevator: a giant tower of blocks. They have K (1 <= K <= 400) different types of blocks with which to build the tower. Each block of type i has height h_i (1 <= h_i <= 100) and is available in quantity c_i (1 <= c_i <= 10). Due to possible damage caused by cosmic rays, no part of a block of type i can exceed a maximum altitude a_i (1 <= a_i <= 40000).
Help the cows build the tallest space elevator possible by stacking blocks on top of each other according to the rules.
Input
* Line 1: A single integer, K
* Lines 2..K+1: Each line contains three space-separated integers: h_i, a_i, and c_i. Line i+1 describes block type i.
Output
* Line 1: A single integer H, the maximum height of a tower that can be built
Sample Input
3 7 40 3 5 23 8 2 52 6
Sample Output
48
Hint
OUTPUT DETAILS:
From the bottom: 3 blocks of type 2, below 3 of type 1, below 6 of type 3. Stacking 4 blocks of type 2 and 3 of type 1 is not legal, since the top of the last type 1 block would exceed height 40.
Source
#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#define inf 0x3f3f3f3f
#define maxn 505
#define maxm 400005
using namespace std;
int n;
struct node
{
int a,h,c;
}a[maxn];
int dp[maxm];
bool cmp(node a,node b)
{
return a.a<b.a;
}
int main()
{
while(~scanf("%d",&n))
{memset(dp,0,sizeof(dp));
for(int i=1;i<=n;i++)
{
scanf("%d%d%d",&a[i].h,&a[i].a,&a[i].c);
}
sort(a+1,a+n+1,cmp);
int maxx=0;
for(int i=1;i<=n;i++)
{
for(int j=1;j<=a[i].c;j++)
for(int k=a[i].a;k>=a[i].h;k--)
{dp[k]=max(dp[k],dp[k-a[i].h]+a[i].h);
if(dp[k]>maxx)
maxx=dp[k];
}
}
printf("%d\n",maxx);
}
return 0;
}