Submission #1035871

#	Time	Username	Problem	Language	Result	Execution time	Memory
1035871		DucNguyen2007	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	442 ms	97856 KiB

skyscraper

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define pii pair<int,int>
#define pll pair<ll,ll>
#define fi first
#define se second
const int maxN=3e4+5,BLOCK=sqrt(maxN);
const ll inf=2e18;
int n,m,b[maxN+1],p[maxN+1],block,cnt[maxN+1];
ll d[maxN+1][BLOCK+1];
struct duongdi
{
    int u,power;
    ll w;
    bool operator < (const duongdi &o)const
    {
        return w>o.w;
    }
};
vector<duongdi> adj[maxN+1];
priority_queue<duongdi> pq;
vector<int> vec[maxN+1];
void CO(int u,int v,int pw,int power,int w)
{
    if(d[v][pw]>d[u][power]+w)
    {
        d[v][pw]=d[u][power]+w;
        pq.push({v,pw,d[v][pw]});
    }
}
int main()
{
    //freopen("","r",stdin);
    //freopen("","w",stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin>>n>>m;
    block=sqrt(n);
    for(int i=0;i<m;i++)
    {
        cin>>b[i]>>p[i];
        if(p[i]<=block)
        {
            vec[b[i]].push_back(p[i]);
        }
        else cnt[b[i]]++;
    }
    for(int i=0;i<m;i++)
    {
        if(p[i]<=block)
        {
            continue;
        }
        for(int j=b[i]+p[i];j<n;j+=p[i])
        {
            adj[b[i]].push_back({j,0,(j-b[i])/p[i]});
        }
        for(int j=b[i]-p[i];j>=0;j-=p[i])
        {
            adj[b[i]].push_back({j,0,(b[i]-j)/p[i]});
        }
    }
    for(int i=0;i<n;i++)
    {
        for(int j=0;j<=block;j++)
        {
            d[i][j]=inf;
        }
    }
    if(p[0]<=block)
    {
        d[b[0]][p[0]]=0;
        pq.push({b[0],p[0],0});
    }
    else
    {
        d[b[0]][0]=0;
        pq.push({b[0],0,0});
    }
    while(!pq.empty())
    {
        duongdi tmp=pq.top();
        pq.pop();
        int u=tmp.u,power=tmp.power;
        ll w=tmp.w;
        //cout<<u<<" "<<power<<" "<<w<<'\n';
        if(u==b[1])
        {
            cout<<d[u][power];
            return 0;
        }
        if(d[u][power]<w)
        {
            continue;
        }
        if(power>0)
        {
            if(u+power<n)
            {
                CO(u,u+power,power,power,1);
            }
            if(u-power>=0)
            {
                CO(u,u-power,power,power,1);
            }
            if(cnt[u]>0)
            {
                CO(u,u,0,power,0);
            }
        }
        else
        {
            for(auto i:adj[u])
            {
                CO(u,i.u,0,power,i.w);
            }
        }
        for(auto i:vec[u])
        {
            CO(u,u,i,power,0);
        }
    }
    cout<<-1;
}

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