이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.
#include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF = (int)1e18;
int ferries(int n , int m , vector<vector<pair<int , int>>> adj) {
vector<int> dp(n , -1);
function<long long(int)> Solve = [&](int node) -> long long {
if (node == n - 1) {
return 0;
}
if (dp[node] != -1) {
return dp[node];
}
vector<int> d;
for (auto x : adj[node]) {
d.push_back(Solve(x.first));
}
sort(d.begin() , d.end());
vector<int> s;
for (int i = 0 ; i < (int)adj[node].size() ; i += 1) {
s.push_back(adj[node][i].second);
}
sort(s.begin() , s.end());
auto Get = [&]() {
int val = INF;
for (int i = 0 ; i < (int)s.size() ; i += 1) {
val = min(val , s[i] + d[(int)s.size() - i - 1]);
}
return val;
};
int res = Get();
reverse(s.begin() , s.end());
reverse(d.begin() , d.end());
res = max(res , Get());
return dp[node] = res;
};
int res = Solve(0);
return res;
}
int32_t main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n , m;
cin >> n >> m;
vector<vector<pair<int , int>>> adj(n) , rev(n);
vector<vector<int>> edges(n);
for (int i = 0 ; i < m ; i += 1) {
int a , b , c;
cin >> a >> b >> c;
a -= 1 , b -= 1;
edges[a].push_back(c);
adj[a].emplace_back(b , c);
rev[b].emplace_back(a , c);
}
bool ok = true;
for (int i = 1 ; i < n - 1 ; i += 1) {
ok &= ((int)adj[i].size() == 1);
}
if (ok) {
int res = ferries(n , m , adj);
cout << res << '\n';
return 0;
}
for (int i = 0 ; i < n ; i += 1) {
sort(edges[i].begin() , edges[i].end());
}
#define pi pair<int , int>
priority_queue<pi , vector<pi> , greater<pi>> pq;
vector<int> d(n , INF);
d[n - 1] = 0;
pq.emplace(d[n - 1] , n - 1);
while (!pq.empty()) {
auto t = pq.top();
pq.pop();
if (d[t.second] != t.first) continue;
for (int i = 0 ; i < (int)rev[t.second].size() ; i += 1) {
auto node = rev[t.second][i];
vector<pair<int , int>> c2;
for (auto x : adj[node.first]) {
c2.emplace_back(d[x.first] , x.first);
}
sort(c2.begin() , c2.end());
for (int j = 0 ; j < (int)edges[node.first].size() ; j++) {
int new_id = (int)edges[node.first].size() - j - 1;
int id = c2[new_id].second;
if (id == t.second) {
if (d[node.first] > t.first + edges[node.first][j]) {
d[node.first] = t.first + edges[node.first][j];
pq.emplace(d[node.first] , node.first);
}
break;
}
else continue;
}
}
}
cout << d[0] << '\n';
return 0;
}
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |