oj.uz

Submission #522051

# Submission time Handle Problem Language Result Execution time Memory
522051 2022-02-03T16:23:12 Z DanerZein Aesthetic (NOI20_aesthetic) C++14
20 / 100
 593 ms 37328 KB 
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll,int> ii;
typedef vector<int> vi;
const int MAX_N=3e5+10;
const ll MAX=1e15;
ll ma[MAX_N];
ll dis[MAX_N];
vector<vi> G;
vector<ll> a,b,w;
int n,m;
bool pri[MAX_N];
bool bri[MAX_N],vis[MAX_N];
int num[MAX_N],low[MAX_N];
int it=0;
void bridge(int u,int p){
  num[u]=low[u]=it++;
  vis[u]=1;
  for(auto &v:G[u]){
    int y;
    if(u==a[v]) y=b[v];
    else y=a[v];
    if(!vis[y]){
      bridge(y,u);
      if(low[y]>num[u]){
	bri[v]=1;
      }
      low[u]=min(low[u],low[y]);
    }
    else
      if(y!=p)
	low[u]=min(low[u],num[v]);
  }
}
vector<ii> bfs(int u){
  for(int i=0;i<n;i++) dis[i]=MAX;
  dis[u]=0;
  priority_queue<ii, vector<ii>, greater<ii> > pq;
  pq.push(ii(0,u));
  while(!pq.empty()){
    int x=pq.top().second;
    int k=pq.top().first;
    pq.pop();
    for(auto &v:G[x]){
      int y;
      if(x==a[v]) y=b[v];
      else y=a[v];
      if(dis[y]>dis[x]+w[v]){
	dis[y]=dis[x]+w[v];
	pq.push(ii(dis[y],y));
      }
    }
  }
  memset(pri,0,sizeof pri);
  vector<ii> path;
  int st,en;
  if(u==0){
    en=0; st=n-1;
  }
  else{
    st=0; en=n-1;
  }
  u=st;
  while(u!=en){
    int id=-1;
    ll mi=MAX;
    for(auto &v:G[u]){
      int y;
      if(u==a[v]) y=b[v];
      else y=a[v];
      if(mi>dis[y]){
	id=v; mi=dis[y];
      }
    }
    if(u==a[id]) u=b[id];
    else u=a[id];
    path.push_back(ii(u,id));
  }
  reverse(path.begin(),path.end());
  return path;
}
int main(){
  cin>>n>>m;
  G.resize(n+1);
  bool sw=0;
  for(int i=0;i<m;i++){
    int x,y,z; cin>>x>>y>>z;
    x--; y--;
    if(z!=1) sw=1;
    a.push_back(x);
    b.push_back(y);
    w.push_back(z);
    G[x].push_back(i);
    G[y].push_back(i);
  }
  ma[m]=0;
  for(int i=m-1;i>=0;i--)
    ma[i]=max(ma[i+1],w[i+1]);
  ll res=0;
  vector<ii> path=bfs(0);
  if(m==n-1){
    for(int i=0;i<path.size();i++){
      int id=path[i].second;
      if(id==m-1) continue;
      ll rp=dis[n-1]+ma[id];
      res=max(res,rp);
    }
  }
  else{
    if(m==n || !sw){
      bridge(0,0);
      if(!sw){
	bool r1=0;
	for(int i=0;i<m-1;i++){
	  if(bri[i]) r1=1; 
	}
	res=dis[n-1]+r1;
      }
      else{
	
      }
    }
    else{
      for(int i=0;i<m-1;i++){
	w[i]+=ma[i];
	bfs(0);
	res=max(res,dis[n-1]);
	w[i]-=ma[i];
      }
      
    }
  }
  cout<<res<<endl;
}

Compilation message

Aesthetic.cpp: In function 'std::vector<std::pair<long long int, int> > bfs(int)':
Aesthetic.cpp:43:9: warning: unused variable 'k' [-Wunused-variable]
   43 |     int k=pq.top().first;
      |         ^
Aesthetic.cpp: In function 'int main()':
Aesthetic.cpp:103:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  103 |     for(int i=0;i<path.size();i++){
      |                 ~^~~~~~~~~~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 588 KB Output is correct
2 Correct 2 ms 588 KB Output is correct
3 Correct 2 ms 620 KB Output is correct
4 Correct 2 ms 588 KB Output is correct
5 Correct 1 ms 588 KB Output is correct
6 Correct 2 ms 588 KB Output is correct
7 Correct 1 ms 588 KB Output is correct
8 Correct 2 ms 588 KB Output is correct

Subtask #2
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 588 KB Output is correct
2 Correct 2 ms 588 KB Output is correct
3 Correct 2 ms 620 KB Output is correct
4 Correct 2 ms 588 KB Output is correct
5 Correct 1 ms 588 KB Output is correct
6 Correct 2 ms 588 KB Output is correct
7 Correct 1 ms 588 KB Output is correct
8 Correct 2 ms 588 KB Output is correct
9 Correct 354 ms 796 KB Output is correct
10 Correct 381 ms 792 KB Output is correct
11 Correct 253 ms 792 KB Output is correct
12 Correct 272 ms 788 KB Output is correct
13 Correct 165 ms 716 KB Output is correct
14 Correct 179 ms 760 KB Output is correct
15 Correct 171 ms 716 KB Output is correct
16 Correct 175 ms 700 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 531 ms 29440 KB Output is correct
2 Correct 517 ms 29616 KB Output is correct
3 Correct 526 ms 29252 KB Output is correct
4 Correct 525 ms 29192 KB Output is correct
5 Correct 514 ms 29476 KB Output is correct
6 Correct 576 ms 29984 KB Output is correct
7 Correct 539 ms 29828 KB Output is correct
8 Correct 532 ms 30104 KB Output is correct

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 593 ms 33268 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 496 ms 37328 KB Output is correct
2 Correct 307 ms 33580 KB Output is correct
3 Incorrect 331 ms 30176 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #6
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 496 ms 37328 KB Output is correct
2 Correct 307 ms 33580 KB Output is correct
3 Incorrect 331 ms 30176 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #7
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 588 KB Output is correct
2 Correct 2 ms 588 KB Output is correct
3 Correct 2 ms 620 KB Output is correct
4 Correct 2 ms 588 KB Output is correct
5 Correct 1 ms 588 KB Output is correct
6 Correct 2 ms 588 KB Output is correct
7 Correct 1 ms 588 KB Output is correct
8 Correct 2 ms 588 KB Output is correct
9 Correct 354 ms 796 KB Output is correct
10 Correct 381 ms 792 KB Output is correct
11 Correct 253 ms 792 KB Output is correct
12 Correct 272 ms 788 KB Output is correct
13 Correct 165 ms 716 KB Output is correct
14 Correct 179 ms 760 KB Output is correct
15 Correct 171 ms 716 KB Output is correct
16 Correct 175 ms 700 KB Output is correct
17 Correct 531 ms 29440 KB Output is correct
18 Correct 517 ms 29616 KB Output is correct
19 Correct 526 ms 29252 KB Output is correct
20 Correct 525 ms 29192 KB Output is correct
21 Correct 514 ms 29476 KB Output is correct
22 Correct 576 ms 29984 KB Output is correct
23 Correct 539 ms 29828 KB Output is correct
24 Correct 532 ms 30104 KB Output is correct
25 Incorrect 593 ms 33268 KB Output isn't correct
26 Halted 0 ms 0 KB -