记录编号 |
565240 |
评测结果 |
AAAAAAAAAA |
题目名称 |
旅游纪念 |
最终得分 |
100 |
用户昵称 |
yrtiop |
是否通过 |
通过 |
代码语言 |
C++ |
运行时间 |
0.343 s |
提交时间 |
2021-10-19 13:30:56 |
内存使用 |
7.92 MiB |
显示代码纯文本
#include <cstdio>
#include <cstring>
#include <queue>
#include <algorithm>
using namespace std;
const int maxn = 200005;
int head[maxn],ver[maxn],nxt[maxn],cnt,dis[maxn];
int Head[maxn],Ver[maxn],Nxt[maxn],Cnt,Dis[maxn];
int dist[maxn],Dist[maxn],qwq[maxn],qaq[maxn];
void Add(int u,int v,int t) {
Ver[++ Cnt] = v;
Dis[Cnt] = t;
Nxt[Cnt] = Head[u];
Head[u] = Cnt;
return ;
}
int n,m,price[maxn];
void add(int u,int v,int t) {
ver[++ cnt] = v;
dis[cnt] = t;
nxt[cnt] = head[u];
head[u] = cnt;
return ;
}
queue<int> q;
bool vis[maxn];
void init(int* a,int val) {
for(int i = 1;i <= n;++ i){
a[i] = val;
}
return ;
}
void init(bool* a,bool val) {
for(int i = 1;i <= n;++ i) {
a[i] = val;
}
return ;
}
void SPFA_dis(int head[maxn],int ver[maxn << 1],int nxt[maxn << 1],int dist[maxn],int s) {
while(!q.empty())q.pop();
init(vis , false);
init(dist , 0x3f3f3f3f);
dist[s] = 0;
q.push(s);
vis[s] = true;
while(!q.empty()) {
int u = q.front();
q.pop();
vis[u] = false;
for(int i = head[u];i;i = nxt[i]) {
int v = ver[i],w = dis[i];
if(dist[v] > dist[u] + w) {
dist[v] = dist[u] + w;
if(!vis[v]) {
vis[v] = true;
q.push(v);
}
}
}
}
return ;
}
void SPFA(int head[maxn],int ver[maxn << 1],int nxt[maxn << 1],int dist[maxn],int s,bool p) {
while(!q.empty())q.pop();//infect BFS
init(vis , false);
if(p)init(qaq , 0x3f3f3f3f);//卖出
else init(qwq , 0x3f3f3f3f);//买入
if(p)qaq[s] = -price[s];
else qwq[s] = price[s];
q.push(s);
vis[s] = true;
while(!q.empty()) {
int u = q.front();
q.pop();
vis[u] = false;
for(int i = head[u];i;i = nxt[i]) {
int v = ver[i];
if(v == s)continue ;
if(p) {
int t = min(qaq[u] + dis[i] , dist[u] + dis[i] - price[v]);
if(qaq[v] > t) {
qaq[v] = t;
if(!vis[v]) {
q.push(v);
vis[v] = true;
}
}
}
else {
int t = min(qwq[u] + dis[i] , dist[u] + dis[i] + price[v]);
if(qwq[v] > t) {
qwq[v] = t;
if(!vis[v]) {
q.push(v);
vis[v] = true;
}
}
}
}
}
return ;
}
int main() {
freopen("keepsake.in","r",stdin);
freopen("keepsake.out","w",stdout);
scanf("%d%d",&n,&m);
for(int i = 1;i <= m;++ i) {
int u,v,t;
scanf("%d%d%d",&u,&v,&t);
add(u , v , t);
Add(v , u , t);
}
for(int i = 1;i <= n;++ i)scanf("%d",&price[i]);
SPFA_dis(head , ver , nxt , dist , 1);
SPFA_dis(Head , Ver , Nxt , Dist , n);
SPFA(head , ver , nxt , dist , 1 , false);
SPFA(Head , Ver , Nxt , Dist , n , true);
int ans = 0x3f3f3f3f;
for(int i = 1;i <= n;++ i) {
ans = min(ans , qaq[i] + qwq[i]);
}
printf("%d",ans);
fclose(stdin);
fclose(stdout);
return 0;
}