| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 705699 |
2023-03-05T01:39:06 Z |
cig32 |
Olympic Bus (JOI20_ho_t4) |
C++17 |
|
761 ms |
10008 KB |
#include <bits/stdc++.h>
#define int long long
using namespace std;
struct edge {
int u, v, c, d;
};
int n, m;
int dist1[232][232];
int distn[232][232];
int rev1[232][232];
int revn[232][232];
int refer;
bool cmp5(pair<pair<int,int>,int> x, pair<pair<int,int>,int> y) {
return revn[refer][x.first.first] + x.first.second < revn[refer][y.first.first] + y.first.second;
}
bool cmp6(pair<pair<int,int>,int> x, pair<pair<int,int>,int> y) {
return rev1[refer][x.first.first] + x.first.second < rev1[refer][y.first.first] + y.first.second;
}
mt19937_64 rng((int) std::chrono::steady_clock::now().time_since_epoch().count());
int rnd(int x, int y) {
return uniform_int_distribution<int>(x, y)(rng);
}
int32_t main() {
ios::sync_with_stdio(0);
cin.tie(0);
int n, m;
cin >> n >> m;
edge e[m+1];
for(int i=1; i<=m; i++) {
cin >> e[i].u >> e[i].v >> e[i].c >> e[i].d;
}
for(int i=0; i<=n; i++) {
for(int j=0; j<=n; j++) {
dist1[i][j] = distn[i][j] = rev1[i][j] = revn[i][j] = 1e9 + 4e8;
}
dist1[i][1] = 0;
distn[i][n] = 0;
rev1[i][1] = 0;
revn[i][n] = 0;
}
for(int b=0; b<=n; b++) {
vector<pair<int, int> > adj[n+1], rev[n+1];
bool vis[n+1];
for(int i=1; i<=m; i++) {
if(e[i].u != b && e[i].v != b) {
adj[e[i].u].push_back({e[i].v, e[i].c});
rev[e[i].v].push_back({e[i].u, e[i].c});
}
}
priority_queue<pair<int,int>, vector<pair<int,int> >, greater<pair<int,int> > > pq;
for(int i=1; i<=n; i++) pq.push({dist1[b][i], i});
for(int i=1; i<=n; i++) vis[i] = 0;
while(pq.size()) {
pair<int,int> t = pq.top(); pq.pop();
if(!vis[t.second]) {
for(pair<int, int> x: adj[t.second]) {
if(!vis[x.first] && dist1[b][x.first] > dist1[b][t.second]+x.second) {
dist1[b][x.first] = dist1[b][t.second]+x.second;
pq.push({dist1[b][x.first], x.first});
}
}
}
}
for(int i=1; i<=n; i++) pq.push({distn[b][i], i});
for(int i=1; i<=n; i++) vis[i] = 0;
while(pq.size()) {
pair<int,int> t = pq.top(); pq.pop();
if(!vis[t.second]) {
for(pair<int, int> x: adj[t.second]) {
if(!vis[x.first] && distn[b][x.first] > distn[b][t.second]+x.second) {
distn[b][x.first] = distn[b][t.second]+x.second;
pq.push({distn[b][x.first], x.first});
}
}
}
}
for(int i=1; i<=n; i++) pq.push({rev1[b][i], i});
for(int i=1; i<=n; i++) vis[i] = 0;
while(pq.size()) {
pair<int,int> t = pq.top(); pq.pop();
if(!vis[t.second]) {
for(pair<int, int> x: rev[t.second]) {
if(!vis[x.first] && rev1[b][x.first] > rev1[b][t.second]+x.second) {
rev1[b][x.first] = rev1[b][t.second]+x.second;
pq.push({rev1[b][x.first], x.first});
}
}
}
}
for(int i=1; i<=n; i++) pq.push({revn[b][i], i});
for(int i=1; i<=n; i++) vis[i] = 0;
while(pq.size()) {
pair<int,int> t = pq.top(); pq.pop();
if(!vis[t.second]) {
for(pair<int, int> x: rev[t.second]) {
if(!vis[x.first] && revn[b][x.first] > revn[b][t.second]+x.second) {
revn[b][x.first] = revn[b][t.second]+x.second;
pq.push({revn[b][x.first], x.first});
}
}
}
}
}
int ans = dist1[0][n] + distn[0][1];
vector<pair<int,int> > adj[n+1], rev[n+1];
vector<int> adj_id[n+1];
for(int i=1; i<=m; i++) {
adj_id[e[i].u].push_back(i);
adj[e[i].u].push_back({e[i].v, e[i].c});
rev[e[i].v].push_back({e[i].u, e[i].c});
}
int cnt[n+1][n+1];
for(int i=0; i<=n; i++) {
for(int j=0; j<=n; j++) {
cnt[i][j] = 0;
}
}
for(int i=1; i<=m; i++) {
cnt[e[i].u][e[i].v]++;
}
int opt1[n+1], opt2[n+1], opt3[n+1], opt4[n+1];
for(int i=1; i<=n; i++) {
opt1[i] = opt2[i] = opt3[i] = opt4[i] = 1e9 + 4e8;
for(pair<int, int> x: adj[i]) {
opt1[i] = min(opt1[i], x.second + revn[i][x.first]);
opt3[i] = min(opt3[i], x.second + rev1[i][x.first]);
}
for(pair<int, int> x: rev[i]) {
opt2[i] = min(opt2[i], dist1[i][x.first] + x.second);
opt4[i] = min(opt4[i], distn[i][x.first] + x.second);
}
}
vector<pair<pair<int,int>, int> > opt5[n+1], opt6[n+1];
for(int i=1; i<=n; i++) {
for(int j=0; j<adj[i].size(); j++) {
opt5[i].push_back({adj[i][j], adj_id[i][j]});
}
refer = i;
sort(opt5[i].begin(), opt5[i].end(), cmp5);
for(int j=0; j<adj[i].size(); j++) {
opt6[i].push_back({adj[i][j], adj_id[i][j]});
}
sort(opt6[i].begin(), opt6[i].end(), cmp6);
}
for(int i=1; i<=m; i++) {
int forward, backward;
forward = dist1[e[i].u][e[i].v] + e[i].c;
int mi = (e[i].u == n ? 0 : 1e9 + 4e8);
mi = min(mi, opt1[e[i].u]);
forward += mi;
forward = min(forward, dist1[e[i].u][n]);
int pt1 = (e[i].u == 1 ? 0 : 1e9 + 4e8);
int pt2 = (e[i].u == n ? 0 : 1e9 + 4e8);
pt1 = min(pt1, opt2[e[i].u]);
for(pair<pair<int,int>, int> x: opt5[e[i].u]) {
if(x.second == i) {
continue;
}
pt2 = min(pt2, revn[e[i].u][x.first.first] + x.first.second);
break;
}
forward = min(forward, pt1 + pt2);
backward = distn[e[i].u][e[i].v] + e[i].c;
mi = (e[i].u == 1 ? 0 : 1e9 + 4e8);
mi = min(mi, opt3[e[i].u]);
backward += mi;
backward = min(backward, distn[e[i].u][1]);
pt1 = (e[i].u == n ? 0 : 1e9 + 4e8);
pt2 = (e[i].u == 1 ? 0 : 1e9 + 4e8);
pt1 = min(pt1, opt4[e[i].u]);
for(pair<pair<int,int>, int> x: opt6[e[i].u]) {
if(x.second == i) {
continue;
}
pt2 = min(pt2, rev1[e[i].u][x.first.first] + x.first.second);
break;
}
backward = min(backward, pt1 + pt2);
ans = min(ans, forward + backward + e[i].d);
//cout << "flip edge " << i << ": " << forward << " + " << backward << " + " << e[i].d << " = " << forward + backward + e[i].d << "\n";
}
cout << (ans <= 1e12 ? ans : -1) << "\n";
}
/*
5 6
1 2 1 10000
2 5 1 10000
5 3 1 10000
2 3 10 1
2 4 1 10000
4 1 1 10000
2 2
1 2 3 4
1 2 3 9
3 4
1 2 3 4
2 3 3 9
2 1 3 10
2 3 3 11
2 7
1 2 1 1
1 2 1 7
1 2 1 3
1 2 1 4
1 2 1 5
1 2 1 6
1 2 1 9
*/
Compilation message
ho_t4.cpp: In function 'int32_t main()':
ho_t4.cpp:137:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
137 | for(int j=0; j<adj[i].size(); j++) {
| ~^~~~~~~~~~~~~~
ho_t4.cpp:142:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
142 | for(int j=0; j<adj[i].size(); j++) {
| ~^~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
46 ms |
2284 KB |
Output is correct |
| 2 |
Incorrect |
16 ms |
2088 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
761 ms |
9996 KB |
Output is correct |
| 2 |
Correct |
727 ms |
9836 KB |
Output is correct |
| 3 |
Correct |
727 ms |
10008 KB |
Output is correct |
| 4 |
Correct |
60 ms |
2360 KB |
Output is correct |
| 5 |
Correct |
42 ms |
2284 KB |
Output is correct |
| 6 |
Incorrect |
22 ms |
2116 KB |
Output isn't correct |
| 7 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
49 ms |
2164 KB |
Output is correct |
| 2 |
Incorrect |
18 ms |
2092 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
46 ms |
2284 KB |
Output is correct |
| 2 |
Incorrect |
16 ms |
2088 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
