| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 882230 | kokoue | Evacuation plan (IZhO18_plan) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
using namespace std;
int n,m,k,q;
int npp[50001];
bool is_npp[100001];
vector<pair<int,int>> edges[50001];
vector<int> sp(50001,INT_MAX);
int furthest[50001][50001];
void dijkstra(int start)
{
// printf("Dijkstra %d: ",start);
priority_queue<pair<int,int>> q;
vector<int> dist(n+1,INT_MAX);
q.push({0,start});
dist[start]=0;
sp[start]=0;
while(!q.empty())
{
// printf("in while: %d->%d \n",q.top().second,q.top().first);
int curr=q.top().second;
int currDist=-q.top().first;
q.pop();
if(dist[curr]<currDist) continue;
for(auto edge:edges[curr])
{
int next=edge.first;
int weight=edge.second;
if(dist[curr]+weight<dist[next])
{
dist[next]=dist[curr]+weight;
sp[next]=min(sp[next],dist[next]);
q.push({-dist[next],next});
}
}
}
/* printf("Dijkstra %d: ",start);
for(int i=0;i<=n;i++)
{
printf("%d:%d ",i,dist[i]);
}
printf("\n");
*/
}
int dijkstra(int start,int finish)
{
// printf("Dijkstra %d->%d: ",start,finish);
priority_queue<pair<int,int>> q;
vector<int> away(n+1,0);
q.push({sp[start],start});
away[start]=sp[start];
while(!q.empty())
{
// printf("in while: %d->%d \n",q.top().second,q.top().first);
int curr=q.top().second;
int currAway=q.top().first;
q.pop();
if(away[curr]>currAway) continue;
for(auto edge:edges[curr])
{
int next=edge.first;
int len=sp[next];
if(away[next]<min(len,away[curr]))
{
away[next]=min(len,away[curr]);
q.push({away[next],next});
}
}
}
for(int i=1;i<=n;i++)
{
if(away[i]!=0) {furthest[start][i]=away[i];furthest[i][start]=away[i];}
}
/* printf("Dijkstra %d->%d: ",start,finish);
for(int i=0;i<=n;i++)
{
printf("%d:%d ",i,away[i]);
}
printf("\n");
*/
return away[finish];
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cin>>n>>m;
int ai,bi,wi;
for(int i=0;i<m;i++)
{
cin>>ai>>bi>>wi;
edges[ai].push_back({bi,wi});
edges[bi].push_back({ai,wi});
}
cin>>k;
for(int i=0;i<k;i++)
{
cin>>npp[i];
is_npp[npp[i]]=true;
dijkstra(npp[i]);
}
cin>>q;
int si,ti;
for(int i=0;i<q;i++)
{
cin>>si>>ti;
if(is_npp[si] || is_npp[ti]) {printf("0\n");continue;}
if(furthest[si][ti]!=0) {printf("%d\n",furthest[si][ti]);continue;}
printf("%d\n",dijkstra(si,ti));
}
}