| # | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
|---|---|---|---|---|---|---|---|
| 1181166 | Szymon_Pilipczuk | Olympic Bus (JOI20_ho_t4) | C++20 | 0 ms | 0 KiB |
#include
#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
long long k[50000][4];
long long inf = (long long)1000000000*1000000000;
long long dis[4][200];
vector<long long> dis3[4][200];
map<vector<long long>,int> kr;
vector<vector<vector<long long>>> gr[2];
priority_queue<vector<long long>> pq;
void dk(long long v,long long c,long long p)
{
for(int i : gr[p%2][v])
{
if(dis[p][i[0]] > c+i[1])
{
pq.push({-1*(c+i[1]),i[0],p});
dis[p][i[0]] = i[1]+c;
if(p%2 == 0)
{
dis3[p][i[0]] = {v,i[0],i[1],i[2]};
}
else
{
dis3[p][i[0]] = {i[0],v,i[1],i[2]};
}
}
}
}
priority_queue<vector<long long>> pq2;
long long dis2[200];
void dk2(long long c,long long v)
{
for(int i = 0;i<gr[0][v].size();i++)
{
if(dis2[gr[0][v][i][0]] > c+gr[0][v][i][1])
{
pq2.push({-1*(c+gr[0][v][i][1]),gr[0][v][i][0]});
dis2[gr[0][v][i][0]] = c+gr[0][v][i][1];
}
}
}
void del()
{
for(int i = 0;i<200;i++)
{
dis2[i] = inf;
}
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n,m;
cin>>n>>m;
gr[0].resize(n);
gr[1].resize(n);
for(int i = 0;i<4;i++)
{
for(int j = 0;j<n;j++)
{
dis[i][j] = inf;
}
}
for(int i = 0;i<m;i++)
{
long long u,v,c,d;
cin>>u>>v>>c>>d;
u--;v--;
kr[{u,v,c,d}] = i;
gr[0][u].push_back({v,c,d});
gr[1][v].push_back({u,c,d});
k[i][0] = u;
k[i][1] = v;
k[i][2] = c;
k[i][3] = d;
}
pq.push({0,0,0});
pq.push({0,0,1});
pq.push({0,n-1,2});
pq.push({0,n-1,3});
dis[0][0]= 0;
dis[1][0] = 0;
dis[2][n-1] = 0;
dis[3][n-1] = 0;
while(!pq.empty())
{
long long a,b,c;
a = pq.top()[1];
b = pq.top()[0]*-1;
c = pq.top()[2];
pq.pop();
if(dis[c][a] == b)
{
dk(a,b,c);
}
}
unordered_set<long long> sps;
for(int i = 0;i<2;i++)
{
for(int j = 1;j<n;j++)
{
if(dis3[i][j].size() != 0)
{
sps.insert(kr[dis3[i][j]]);
}
}
}
for(int i = 2;i<4;i++)
{
for(int j = 0;j<n-1;j++)
{
if(dis3[i][j].size() != 0)
{
sps.insert(kr[dis3[i][j]]);
}
}
}
long long ans = dis[0][n-1]+dis[2][0];
dis[2][n-1] = 0;
dis[3][n-1] = 0;
dis[0][0] = 0;
dis[1][0] = 0;
for(int i = 0;i<m;i++)
{
if(sps.find(i) == sps.end())
{
ans = min(ans,k[i][3]+min(dis[0][n-1],dis[0][k[i][1]]+k[i][2]+dis[3][k[i][0]])+min(dis[2][0],dis[2][k[i][1]]+k[i][2]+dis[1][k[i][0]]));
}
}
del();
for(int i = 0;i<n;i++)
{
for(int j = 0;j<gr[0][i].size();j++)
{
if(sps.find(kr[{i,gr[0][i][j][0],gr[0][i][j][1],gr[0][i][j][2]}]) != sps.end())
{
long long cu = gr[0][i][j][0];
long long cans = gr[0][i][j][2];
gr[0][i][j][0] = i;
gr[0][cu].push_back({i,gr[0][i][j][1]});
pq2.push({0,0});
dis2[0] = 0;
while(!pq2.empty())
{
long long a = pq2.top()[0]*-1,b = pq2.top()[1];
pq2.pop();
if(dis2[b] == a)
{
dk2(a,b);
}
}
cans += dis2[n-1];
del();
pq2.push({0,n-1});
dis2[n-1] =0 ;
while(!pq2.empty())
{
long long a = pq2.top()[0]*-1,b = pq2.top()[1];
pq2.pop();
if(dis2[b]== a)
{
dk2(a,b);
}
}
cans+=dis2[0];
del();
gr[0][i][j][0] = cu;
gr[0][cu].pop_back();
ans = min(ans,cans);
}
}
}
long long cans = 0;
pq2.push({0,0});
dis2[0] = 0;
while(!pq2.empty())
{
long long a = pq2.top()[0]*-1,b = pq2.top()[1];
pq2.pop();
if(dis2[b] == a)
{
dk2(a,b);
}
}
cans += dis2[n-1];
del();
pq2.push({0,n-1});
dis2[n-1] = 0;
while(!pq2.empty())
{
long long a = pq2.top()[0]*-1,b = pq2.top()[1];
pq2.pop();
if(dis2[b] == a)
{
dk2(a,b);
}
}
cans+=dis2[0];
del();
ans = min(ans,cans);
if(ans >= inf)
{
cout<<-1<<"\n";
}
else
{
cout<<ans<<"\n";
}
}