hdu 5361 2015多校联合训练赛#6 最短路

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Time Limit: 8000/4000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)
Total Submission(s): 67    Accepted Submission(s): 11

Problem Description

There are n soda living in a straight line. soda are numbered by  1,2,…,n  from left to right. The distance between two adjacent soda is 1 meter. Every soda has a teleporter. The teleporter of  i -th soda can teleport to the soda whose distance between  i -th soda is no less than  li  and no larger than  ri . The cost to use  i -th soda's teleporter is  ci .

The  1 -st soda is their leader and he wants to know the minimum cost needed to reach  i -th soda  (1≤i≤n) . 

 

Input

There are multiple test cases. The first line of input contains an integer  T , indicating the number of test cases. For each test case:

The first line contains an integer  n   (1≤n≤2×105) , the number of soda. 
The second line contains  n  integers  l1,l2,…,ln . The third line contains  n  integers  r1,r2,…,rn . The fourth line contains  n  integers  c1,c2,…,cn .  (0≤li≤ri≤n,1≤ci≤109)

 

Output

For each case, output  n  integers where  i -th integer denotes the minimum cost needed to reach  i -th soda. If  1 -st soda cannot reach  i -the soda, you should just output -1.

 

Sample Input

   
   
   
   

    
    
    
    1
5
2 0 0 0 1
3 1 1 0 5
1 1 1 1 1
   
   
   
   

 

Sample Output

   
   
   
   

    
    
    
    0 2 1 1 -1

    
    
    
    
 
     
 
      Hint 
     
If you need a larger stack size, please use #pragma comment(linker, "/STACK:102400000,102400000") and submit your solution using C++. 
    
    
    
    
     
   
   
   
   

 

Source

2015 Multi-University Training Contest 6

求最短路：把一个集合的点看做是一个点，这样就可以用djstra算法做了。然后由于每个点最多标记一次最短路，用set维护一个点集合。

当最短路找到一个一个集合的时候，把这个集合里还存在的点都取出即可。取出后，每个点又可以去两个集合，

再向保存最短路的set里更新集合信息即可。详细看代码。

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<set>
using namespace std;
#define maxn 200007
#define ll long long

int lp[maxn],rp[maxn];
ll cosw[maxn];
ll dist[maxn];


set<int> haha;

struct Node{
    int id;
    ll cost;
};
bool operator < (Node a,Node b){
    if(a.cost == b.cost) return a.id < b.id;
    return a.cost < b.cost;
}

set<Node> mind;

int main(){
    int t,n;
    scanf("%d",&t);
    while(t--){
        scanf("%d",&n);
        for(int i = 0;i < n; i++)
            scanf("%d",&lp[i]);
        for(int i = 0;i < n; i++)
            scanf("%d",&rp[i]);
        for(int i = 0;i < n; i++)
            scanf("%d",&cosw[i]);
        haha.clear();
        mind.clear();
        memset(dist,-1,sizeof(dist));
        dist[0] = 0;

        Node x,y;
        x.id = 0;
        x.cost = cosw[0];
        mind.insert(x);
        for(int i = 1;i < n; i++)
            haha.insert(i);

        set<int>::iterator it,it2;
        while(mind.size() > 0){
            x = *mind.begin();
            mind.erase(mind.begin());

            it = haha.lower_bound(x.id - rp[x.id]);
            while(it != haha.end()  && *it <= x.id - lp[x.id]){
                y.id = *it;
                y.cost = x.cost + cosw[y.id];
                dist[y.id] = x.cost;
                mind.insert(y);
                it2 = it++;
                haha.erase(it2);
            }

            it = haha.lower_bound(x.id + lp[x.id]);
            while(it != haha.end()  && *it <= x.id + rp[x.id]){
                y.id = *it;
                y.cost = x.cost + cosw[y.id];
                dist[y.id] = x.cost;
                mind.insert(y);
                it2 = it++;
                haha.erase(it2);
            }
        }
        for(int  i = 0;i < n; i++){
            if(i) printf(" ");
            printf("%I64d",dist[i]);
        }
        printf("\n");
    }
    return 0;
}