[codeforces938D]Buy a Ticket

time limit per test : 2 seconds
memory limit per test : 256 megabytes

Musicians of a popular band “Flayer” have announced that they are going to “make their exit” with a world tour. Of course, they will visit Berland as well.

There are n cities in Berland. People can travel between cities using two-directional train routes; there are exactly m routes, i-th route can be used to go from city viv_i to city uiu_i (and from uiu_i to viv_i), and it costs wiw_i coins to use this route.

Each city will be visited by “Flayer”, and the cost of the concert ticket in i-th city is ai coins.

You have friends in every city of Berland, and they, knowing about your programming skills, asked you to calculate min2d(i,j)+aj\min 2d(i,j)+a_j the minimum possible number of coins they have to pay to visit the concert. For every city ii you have to compute the minimum number of coins a person from city i has to spend to travel to some city j (or possibly stay in city i), attend a concert there, and return to city i(i (if jji)i).

Formally, for every you have to calculate , where d(i,j)d(i, j) is the minimum number of coins you have to spend to travel from city ii to city jj. If there is no way to reach city jj from city ii, then we consider d(i,j)d(i, j) to be infinitely large.
Input

The first line contains two integers nn and m(2n2105,1m2105)m (2 ≤ n ≤ 2·10^5, 1 ≤ m ≤ 2·10^5).

Then m lines follow, i-th contains three integers vi,uivi, ui and wi(1vi,uin,viwi (1 ≤ v_i, u_i ≤ n, v_i ui,1wi1012)u_i, 1 ≤ w_i ≤ 10^{12}) denoting i-th train route. There are no multiple train routes connecting the same pair of cities, that is, for each (v, u) neither extra (v,u)(v, u) nor (u,v)(u, v) present in input.

The next line contains n integers a1,a2,...ak(1ai1012)a_1, a_2, ... a_k (1 ≤ a_i ≤ 10^{12}) — price to attend the concert in i-th city.
Output

Print n integers. i-th of them must be equal to the minimum number of coins a person from city i has to spend to travel to some city j (or possibly stay in city i), attend a concert there, and return to city i (if j ≠ i).
Examples
Input

4 2
1 2 4
2 3 7
6 20 1 25

Output

6 14 1 25 

Input

3 3
1 2 1
2 3 1
1 3 1
30 10 20

Output

12 10 12 

題意:
給一張無向圖
和每個點的點權aia_i
對於每個點ii求出min2d(i,j)+aj(j!=i)\min 2d(i,j)+a_j(j != i)

題解:
先將所有點邊的權值*2
將所有初始點的答案設爲a[i]a[i]加入優先隊列跑dijkstra即可。

#include<bits/stdc++.h>
#define ll long long
#define pa pair<ll,ll>
using namespace std;
const ll INF=1e18;
bool vis[200004];
ll a[200004];
vector<pa>G[200004];
int n,m;
priority_queue<pa,vector<pa>,greater<pa> >q;
int main(){
    scanf("%d%d",&n,&m);
    for(int i=1;i<=m;i++){
        int u,v;ll w;
        scanf("%d%d%lld",&u,&v,&w);
        w<<=1;
        G[u].push_back({v,w});
        G[v].push_back({u,w});
    }
    for(int i=1;i<=n;i++)scanf("%lld",&a[i]);
    for(int i=1;i<=n;i++){
        q.push({a[i],i});
    }
    while(!q.empty()){
        ll x=q.top().second,pre=q.top().first;
        q.pop();
        if(a[x]!=pre)continue;
        for(pa eg:G[x]){
            int to=eg.first;ll w=eg.second;
            if(a[to]>pre+w){
                a[to]=pre+w;
                q.push({a[to],to});
            }
        }
    }
    for(int i=1;i<=n;i++)printf("%lld ",a[i]);
    puts("");
    return 0;
}
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