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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#781647 | #7883. Takeout Delivering | pcc1 | WA | 314ms | 70560kb | C++14 | 1.8kb | 2024-11-25 16:46:02 | 2024-11-25 16:46:22 |
Judging History
answer
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<vector>
#define int long long
using namespace std;
const int N=1e6+10;
int n,m;
struct node{
int u,v,w;
}a[N];
struct Node{
int fr,to,nxt,w;
}e[N*2];
int f[N],tot,head[N];
void add(int a,int b,int w){
e[++tot].fr=a;
e[tot].nxt=head[a];
head[a]=tot;
e[tot].to=b;
e[tot].w=w;
}
int find(int x){
if(f[x]==x)return x;
return f[x]=find(f[x]);
}
int dis1[N],dis2[N];
void dfs(int u,int fa){
for(int i=head[u];i;i=e[i].nxt){
int v=e[i].to;
if(v==fa)continue;
dis1[v]=max(dis1[u],e[i].w);
dfs(v,u);
}
}
bool cmp(node a,node b){
return a.w<b.w;
}
signed main(){
int ans=2e18;
cin>>n>>m;
for(int i=1;i<=n;i++){
f[i]=i;
}
for(int u,v,w,i=1;i<=m;i++){
cin>>a[i].u>>a[i].v>>a[i].w;
if(a[i].u==1&&a[i].v==n){
ans=min(ans,a[i].w);
}
if(a[i].u==n&&a[i].v==1){
ans=min(ans,a[i].w);
}
}
sort(a+1,a+m+1,cmp);
// for(int i=1;i<=m;i++){
// cout<<a[i].u<<" "<<a[i].v<<":\n";
// }
for(int i=1;i<=m;i++){
int x=find(a[i].u);int y=find(a[i].v);
if(x!=y){
f[x]=y;
add(a[i].u,a[i].v,a[i].w);
add(a[i].v,a[i].u,a[i].w);
}
// add(a[i].u,a[i].v);add(a[i].v,a[i].u);
}
dfs(1,0);
swap(dis2,dis1);
// for(int i=1;i<=n;i++){
// cout<<dis2[i]<<" ";
// }c
// cout<<"\n";
dfs(n,0);
//ans=2e9;
// if(n==300000){
// for(int i=1;i<=n;i++){
// cout<<dis1[i]<<" ";
// }
// }
int cnt=2e9+10;
for(int i=1;i<=m;i++){
if(n==300000)cout<<e[i].w<<" "<<dis1[e[i].fr]<<" "<<dis2[e[i].to]<<"\n";
if(dis1[e[i].fr]<=e[i].w&&dis2[e[i].to]<=e[i].w)cnt=min(cnt,max(dis1[e[i].fr],dis2[e[i].to])+e[i].w);
if(dis2[e[i].fr]<=e[i].w&&dis1[e[i].to]<=e[i].w)cnt=min(cnt,max(dis1[e[i].to],dis2[e[i].fr])+e[i].w);
}
cout<<cnt<<"\n";
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 25408kb
input:
4 6 1 2 2 1 3 4 1 4 7 2 3 1 2 4 3 3 4 9
output:
5
result:
ok 1 number(s): "5"
Test #2:
score: -100
Wrong Answer
time: 314ms
memory: 70560kb
input:
300000 299999 80516 80517 597830404 110190 110191 82173886 218008 218009 954561262 250110 250111 942489774 66540 66541 156425292 34947 34948 239499776 273789 273790 453201232 84428 84429 439418398 98599 98600 326095035 55636 55637 355015760 158611 158612 684292473 43331 43332 43265001 171621 171622 ...
output:
1925 999980151 999996532 1925 999980151 999996532 11047 999260250 999996532 11047 999260250 999996532 11374 999996532 999995165 11374 999996532 999995165 14882 999980151 999996532 14882 999980151 999996532 22481 999964329 999996532 22481 999964329 999996532 24168 999996532 999995165 24168 999996532 ...
result:
wrong answer 1st numbers differ - expected: '1999991697', found: '1925'