#include <bits/stdc++.h>
//#include "bits_stdc++.h"
#define f first
#define s second
#define mp make_pair
#define pb push_back
#define lb lower_bound
#define ub upper_bound
//#define input(x) scanf("%lld", &x);
//#define print(x, y) printf("%lld%c", x, y);
#define show(x) cerr << #x << " is " << x << endl;
#define show2(x,y) cerr << #x << " is " << x << " " << #y << " is " << y << endl;
#define show3(x,y,z) cerr << #x << " is " << x << " " << #y << " is " << y << " " << #z << " is " << z << endl;
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ld, ll> pd;
typedef pair<string, ll> psl;
typedef pair<ll, ll> pi;
typedef pair<ll, pi> pii;
ll n, m;
vector<ll> height;
vector<ll> adj[200005];
pi edges[400005];
ll const INF = LLONG_MAX/3;
vector<ll> dijkstra(ll from)
{
vector<ll> visited(n+1, false);
vector<ll> dist(n+1, INF);
dist[from] = 0;
priority_queue<pi, vector<pi>, greater<pi> > pq;
pq.push(mp(0, from));
while (pq.size())
{
ll c = pq.top().s;
pq.pop();
if (visited[c]) continue;
visited[c] = true;
for (ll u: adj[c])
{
ll neww = max(dist[c]+1, height[u]);
if (dist[u]>neww)
{
dist[u] = neww;
pq.push(mp(neww, u));
}
}
}
return dist;
}
int main()
{
cin >> n >> m;
height.resize(n+1);
for (ll i=1; i<=n; ++i) cin >> height[i];
for (ll i=0; i<m; ++i)
{
ll x, y;
cin >> x >> y;
edges[i].f = x, edges[i].s = y;
adj[x].pb(y);
adj[y].pb(x);
}
vector<ll> up, down;
up = dijkstra(1); down = dijkstra(n);
ll ans = LLONG_MAX;
// if maintain for 0 sec
for (ll i=2; i<n; ++i)
{
ans = min(ans, max(up[i], down[i])*2);
}
// if maintain for 1 sec
for (ll i=0; i<m; ++i)
{
pi x = edges[i];
if (x.f==1 || x.s==1 || x.f==n || x.s==n) continue;
ans = min(ans, max(up[x.f], down[x.s])*2+1);
ans = min(ans, max(up[x.s], down[x.f])*2+1);
}
cout << ans << endl;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
7000 KB |
Output is correct |
2 |
Correct |
143 ms |
25576 KB |
Output is correct |
3 |
Correct |
186 ms |
27324 KB |
Output is correct |
4 |
Correct |
206 ms |
27576 KB |
Output is correct |
5 |
Correct |
180 ms |
28124 KB |
Output is correct |
6 |
Correct |
225 ms |
28032 KB |
Output is correct |
7 |
Correct |
189 ms |
28092 KB |
Output is correct |
8 |
Incorrect |
3 ms |
7004 KB |
Output isn't correct |
9 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
7004 KB |
Output is correct |
2 |
Correct |
3 ms |
7000 KB |
Output is correct |
3 |
Incorrect |
3 ms |
7156 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
7004 KB |
Output is correct |
2 |
Correct |
3 ms |
7000 KB |
Output is correct |
3 |
Incorrect |
3 ms |
7156 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
7000 KB |
Output is correct |
2 |
Correct |
143 ms |
25576 KB |
Output is correct |
3 |
Correct |
186 ms |
27324 KB |
Output is correct |
4 |
Correct |
206 ms |
27576 KB |
Output is correct |
5 |
Correct |
180 ms |
28124 KB |
Output is correct |
6 |
Correct |
225 ms |
28032 KB |
Output is correct |
7 |
Correct |
189 ms |
28092 KB |
Output is correct |
8 |
Incorrect |
3 ms |
7004 KB |
Output isn't correct |
9 |
Halted |
0 ms |
0 KB |
- |