#include <bits/stdc++.h>
using namespace std;
long long inf = (1LL << 62LL);
typedef pair<long long, long long> ii;
vector<ii> adjO[205];
vector<ii> adj[205];
long long dis[205];
int n, m;
long long dij(int s, int t){
fill(dis, dis + (n+1), inf);
priority_queue<ii, vector<ii>, greater<ii> > dtr; /// use greater<int>
dtr.push(ii(0,s));
dis[s] = 0;
///first is minpath, second is vertex
while(!dtr.empty()){
ii cur = dtr.top();
dtr.pop();
for(int j = 0;j < (int) adj[cur.second].size();j++){
ii nei = adj[cur.second][j];
if(nei.first + cur.first < dis[nei.second]){
dis[nei.second] = nei.first + cur.first;
dtr.push(ii(dis[nei.second],nei.second));
}
}
}
return dis[t];
}
struct edge{
long long u, v, c, d;
};
vector<edge> edges;
void invert(int u, int v){
for(int j = 0;j < adj[u].size();j++){
if(adj[u][j].second == v){
adj[v].push_back(ii(adj[u][j].first,u));
swap(adj[u][j], adj[u].back());
adj[u].pop_back();
return;
}
}
assert(false);
}
void subtask1(){
long long ans = dij(1, n)+ dij(n, 1);
for(edge e : edges){
invert(e.u, e.v);
ans = min(ans, dij(1,n) + dij(n,1) + e.d);
invert(e.v, e.u);
}
if(ans >= inf) ans = -1;
cout << ans;
exit(0);
}
int main(){
//freopen("i.txt","r",stdin);
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n >> m;
for(int i = 0;i < m;i++){
int u, v, c, d; cin >> u >> v >> c >> d;
edges.push_back({u,v,c,d});
adj[u].push_back(ii(c,v));
}
if(m <= 1000) subtask1();
}
Compilation message
ho_t4.cpp: In function 'void invert(int, int)':
ho_t4.cpp:39:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j = 0;j < adj[u].size();j++){
~~^~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
39 ms |
512 KB |
Output is correct |
2 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
28 ms |
3420 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
41 ms |
512 KB |
Output is correct |
2 |
Incorrect |
6 ms |
384 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
39 ms |
512 KB |
Output is correct |
2 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |