Submission #533090

#	Time	Username	Problem	Language	Result	Execution time	Memory
533090		new_acc	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	292 ms	218468 KiB

skyscraper

#include<bits/stdc++.h>
#define fi first
#define se second
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
const int N=3e4+10;
vector<pair<int,short> > graf[N*20];
pair<short,short>w[N];
int l,num[N];
vector<short> li[300];
bitset<N>bb;
bitset<N*20>vis;
vi kol[1000*1000*4+10];
int n,m;
void single(int x){
	if(li[x].empty()) return;
	for(int i=1;i<=x;i++){
		num[i]=++l;
		graf[l].push_back({i,0});
	}
	for(int i=x+1;i<=n;i++){
		num[i]=++l;
		graf[l].push_back({i,0}),graf[l].push_back({num[i-x],1});
	}
	for(int i=1;i<=n;i++) bb[i]=0;
	for(auto u:li[x]) bb[w[u].fi]=1;
	for(int i=1;i<=n;i++) if(bb[i]) graf[i].push_back({num[i],0});
	for(int i=n;i>=n-x+1;i--){
		num[i]=++l;
		graf[l].push_back({i,0});
	}
	for(int i=n-x;i>=1;i--){
		num[i]=++l;
		graf[l].push_back({i,0}),graf[l].push_back({num[i+x],1});
	}
	for(int i=1;i<=n;i++) if(bb[i]) graf[i].push_back({num[i],0});
}
int Dijkstra(int p,int k){
	kol[0].push_back(p);
	for(int i=0;i<=(int)4e6;i++){
		for(int j=0;j<kol[i].size();j++){
			int v=kol[i][j];
			if(vis[v]) continue;
			vis[v]=1;
			if(v==k) return i;
			for(auto u:graf[v])
				if(!vis[u.fi] and i+u.se<=(int)4e6) kol[i+u.se].push_back(u.fi);
		}
	}
	return -1;
}
void solve(){
	cin>>n>>m;
	l=n;
	int p=sqrt(n)/20;
	for(int i=1;i<=m;i++){
		cin>>w[i].fi>>w[i].se;
		w[i].fi++;
		if(w[i].se>p){
			for(int j=w[i].fi+w[i].se;j<=n;j+=w[i].se) graf[w[i].fi].push_back({j,(j-w[i].fi)/w[i].se});
			for(int j=w[i].fi-w[i].se;j>=1;j-=w[i].se) graf[w[i].fi].push_back({j,(w[i].fi-j)/w[i].se});
		}else li[w[i].se].push_back(i);
	}
	for(int i=1;i<=p;i++) single(i);		
	cout<<Dijkstra(w[1].fi,w[2].fi)<<"\n";
}
int main(){
	ios_base::sync_with_stdio(0),cin.tie(0);
	solve();
}

Compilation message (stderr)

skyscraper.cpp: In function 'int Dijkstra(int, int)':
skyscraper.cpp:43:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |   for(int j=0;j<kol[i].size();j++){
      |               ~^~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 43 / 43