#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define fi first
#define se second
#define ll long long
#define ld long double
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define mpp make_pair
#define ve vector
using namespace std;
using namespace __gnu_pbds;
template<class T> using oset = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
const ll inf = 1e18; const int iinf = 1e9;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T> inline bool chmin(T& a, T b) { return (a > b ? a = b, 1 : 0); }
template <typename T> inline bool chmax(T& a, T b) { return (a < b ? a = b, 1 : 0); }
const int N = 3e5 + 10;
const int M = 3e5 + 10;
ve<int> gr[N];
int n;
array<int,3> edges[M];
inline int go(const int &ID, const int &v) { return v ^ edges[ID][0] ^ edges[ID][1]; }
inline ve<ll> dij(const int &s) {
ve<ll> d(n, inf); d[s] = 0;
set<pll> st; st.insert({d[s], s});
while (sz(st)) {
int v = st.begin()->se;
st.erase(st.begin());
for (auto &id : gr[v]) {
int to = go(id, v);
int w = edges[id][2];
if (d[to] > d[v] + w) {
st.erase({d[to], to});
d[to] = d[v] + w;
st.insert({d[to], to});
}
}
}
return d;
}
inline void solve() {
int m;
cin >> n >> m;
for (int i = 0; i < m; ++i) {
int v, u, w;
cin >> v >> u >> w;
edges[i] = {--v, --u, w};
gr[v].pb(i);
gr[u].pb(i);
}
ve<int> sf(m);
for (int i = m - 2; ~i; --i) {
sf[i] = max(sf[i + 1], edges[i + 1][2]);
}
auto d0 = dij(0);
auto d1 = dij(n - 1);
auto can = [&](const ll &x) -> bool {
int timer = 0;
ve<int> in(n), up(n), used(n);
bool ok = 0;
function<void(int,int)> dfs = [&](int v, int pid) {
used[v] = 1;
in[v] = up[v] = timer++;
for (auto &id : gr[v]) {
int to = go(id, v);
auto &[A, B, w] = edges[id];
ll cs = min(d0[A] + d1[B], d1[A] + d0[B]) + w;
if (cs >= x || id == pid) continue;
if (used[to] == 1) {
chmin(up[v], in[to]);
}
else if (!used[to]) {
dfs(to, id);
chmin(up[v], up[to]);
if (up[to] > in[v] && in[n - 1] >= in[to] && cs + sf[id] >= x) {
ok = 1;
}
}
}
used[v] = 2;
};
dfs(0, -1);
return ok;
};
ll l = d0[n - 1], r = d0[n - 1] + sf[0], mid, ans;
while (l <= r) {
mid = l + r >> 1;
if (can(mid)) ans = mid, l = mid + 1;
else r = mid - 1;
}
cout << ans;
}
signed main() {
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
int q = 1; // cin >> q;
while (q--) solve();
cerr << fixed << setprecision(3) << "Time execution: " << (double)clock() / CLOCKS_PER_SEC << endl;
}
Compilation message
Aesthetic.cpp: In function 'void solve()':
Aesthetic.cpp:117:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
117 | mid = l + r >> 1;
| ~~^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
7380 KB |
Output is correct |
2 |
Correct |
4 ms |
7380 KB |
Output is correct |
3 |
Correct |
5 ms |
7380 KB |
Output is correct |
4 |
Correct |
4 ms |
7380 KB |
Output is correct |
5 |
Correct |
4 ms |
7328 KB |
Output is correct |
6 |
Correct |
4 ms |
7380 KB |
Output is correct |
7 |
Correct |
4 ms |
7380 KB |
Output is correct |
8 |
Correct |
4 ms |
7380 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
7380 KB |
Output is correct |
2 |
Correct |
4 ms |
7380 KB |
Output is correct |
3 |
Correct |
5 ms |
7380 KB |
Output is correct |
4 |
Correct |
4 ms |
7380 KB |
Output is correct |
5 |
Correct |
4 ms |
7328 KB |
Output is correct |
6 |
Correct |
4 ms |
7380 KB |
Output is correct |
7 |
Correct |
4 ms |
7380 KB |
Output is correct |
8 |
Correct |
4 ms |
7380 KB |
Output is correct |
9 |
Correct |
5 ms |
7508 KB |
Output is correct |
10 |
Correct |
5 ms |
7508 KB |
Output is correct |
11 |
Correct |
8 ms |
7652 KB |
Output is correct |
12 |
Correct |
6 ms |
7508 KB |
Output is correct |
13 |
Correct |
5 ms |
7524 KB |
Output is correct |
14 |
Correct |
5 ms |
7508 KB |
Output is correct |
15 |
Correct |
5 ms |
7508 KB |
Output is correct |
16 |
Correct |
5 ms |
7508 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
449 ms |
29512 KB |
Output is correct |
2 |
Correct |
460 ms |
29468 KB |
Output is correct |
3 |
Correct |
465 ms |
29244 KB |
Output is correct |
4 |
Correct |
441 ms |
29288 KB |
Output is correct |
5 |
Correct |
472 ms |
29432 KB |
Output is correct |
6 |
Correct |
459 ms |
29876 KB |
Output is correct |
7 |
Correct |
454 ms |
29700 KB |
Output is correct |
8 |
Correct |
500 ms |
29912 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
468 ms |
29936 KB |
Output is correct |
2 |
Correct |
458 ms |
29548 KB |
Output is correct |
3 |
Correct |
499 ms |
29400 KB |
Output is correct |
4 |
Correct |
447 ms |
29896 KB |
Output is correct |
5 |
Correct |
450 ms |
29464 KB |
Output is correct |
6 |
Correct |
456 ms |
29424 KB |
Output is correct |
7 |
Correct |
454 ms |
29452 KB |
Output is correct |
8 |
Correct |
446 ms |
29656 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
406 ms |
27496 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
406 ms |
27496 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
7380 KB |
Output is correct |
2 |
Correct |
4 ms |
7380 KB |
Output is correct |
3 |
Correct |
5 ms |
7380 KB |
Output is correct |
4 |
Correct |
4 ms |
7380 KB |
Output is correct |
5 |
Correct |
4 ms |
7328 KB |
Output is correct |
6 |
Correct |
4 ms |
7380 KB |
Output is correct |
7 |
Correct |
4 ms |
7380 KB |
Output is correct |
8 |
Correct |
4 ms |
7380 KB |
Output is correct |
9 |
Correct |
5 ms |
7508 KB |
Output is correct |
10 |
Correct |
5 ms |
7508 KB |
Output is correct |
11 |
Correct |
8 ms |
7652 KB |
Output is correct |
12 |
Correct |
6 ms |
7508 KB |
Output is correct |
13 |
Correct |
5 ms |
7524 KB |
Output is correct |
14 |
Correct |
5 ms |
7508 KB |
Output is correct |
15 |
Correct |
5 ms |
7508 KB |
Output is correct |
16 |
Correct |
5 ms |
7508 KB |
Output is correct |
17 |
Correct |
449 ms |
29512 KB |
Output is correct |
18 |
Correct |
460 ms |
29468 KB |
Output is correct |
19 |
Correct |
465 ms |
29244 KB |
Output is correct |
20 |
Correct |
441 ms |
29288 KB |
Output is correct |
21 |
Correct |
472 ms |
29432 KB |
Output is correct |
22 |
Correct |
459 ms |
29876 KB |
Output is correct |
23 |
Correct |
454 ms |
29700 KB |
Output is correct |
24 |
Correct |
500 ms |
29912 KB |
Output is correct |
25 |
Correct |
468 ms |
29936 KB |
Output is correct |
26 |
Correct |
458 ms |
29548 KB |
Output is correct |
27 |
Correct |
499 ms |
29400 KB |
Output is correct |
28 |
Correct |
447 ms |
29896 KB |
Output is correct |
29 |
Correct |
450 ms |
29464 KB |
Output is correct |
30 |
Correct |
456 ms |
29424 KB |
Output is correct |
31 |
Correct |
454 ms |
29452 KB |
Output is correct |
32 |
Correct |
446 ms |
29656 KB |
Output is correct |
33 |
Incorrect |
406 ms |
27496 KB |
Output isn't correct |
34 |
Halted |
0 ms |
0 KB |
- |