Submission #1232395

#	Time	Username	Problem	Language	Result	Execution time	Memory
1232395		alexander707070	Petrol stations (CEOI24_stations)	C++20	18 / 100	62 ms	33348 KiB

Main

#include<bits/stdc++.h>
#define MAXN 70007
using namespace std;

const int inf=2e9;

struct edge{
    int to,cost;
};

int n,K,a,b,c;
long long ans[MAXN],sz[MAXN];
vector<edge> v[MAXN];

void calc(int x,int p){
    sz[x]=1;

    for(auto e:v[x]){
        if(e.to==p)continue;
        calc(e.to,x);

        sz[x]+=sz[e.to];
    }
}

void dfs(int x,int p,int up,long long d){
    
    if(d<0){
        ans[p]+=sz[x];
        d=K-up;
    }

    for(auto e:v[x]){
        if(e.to==p)continue;
        dfs(e.to,x,e.cost,d-e.cost);
    }
}

void solve_slow(){
    for(int i=1;i<=n;i++){
        calc(i,0);
        dfs(i,0,0,K);
    }

    for(int i=1;i<=n;i++){
        cout<<ans[i]<<"\n";
    }
}

int ed[MAXN],m,to[MAXN];
vector<int> tree[MAXN];
int ver[MAXN];

void dfs2(int x,int p){
    for(auto e:v[x]){
        if(e.to==p)continue;

        m++; ed[m]=e.cost;
        ver[m]=x; ver[m+1]=e.to;

        dfs2(e.to,x);
    }
}

void dfs3(int x){
    sz[x]=1;

    for(int i:tree[x]){
        dfs3(i);
        sz[x]+=sz[i];
    }
}

void solve_line(){
    for(int i=1;i<=n;i++){
        if(v[i].size()==1){
            dfs2(i,0); break;
        }
    }

    int pt=1,sum=ed[1];

    for(int i=1;i<=m;i++){
        while(pt<m and sum+ed[pt+1]<=K){
            pt++; sum+=ed[pt];
        }
        to[i]=pt+1;

        sum-=ed[i];
    }

    for(int i=1;i<=m;i++){
        tree[to[i]].push_back(i);
    }
    dfs3(n);

    for(int i=1;i<=n;i++){
        ans[ver[i]]+=(long long) (sz[i]-1) * (n-i);
        tree[i].clear();
    }

    reverse(ed+1,ed+m+1);
    reverse(ver+1,ver+n+1);

    pt=1; sum=ed[1];

    for(int i=1;i<=m;i++){
        while(pt<m and sum+ed[pt+1]<=K){
            pt++; sum+=ed[pt];
        }
        to[i]=pt+1;

        sum-=ed[i];
    }

    for(int i=1;i<=m;i++){
        tree[to[i]].push_back(i);
    }
    dfs3(n);

    for(int i=1;i<=n;i++){
        ans[ver[i]]+=(long long) (sz[i]-1) * (n-i);
    }

    for(int i=1;i<=n;i++){
        cout<<ans[i]<<"\n";
    }
}

long long down[MAXN][11],up[MAXN][11],all[MAXN][11];

void dfs4(int x,int p){

    for(auto e:v[x]){
        if(e.to==p)continue;
        dfs4(e.to,x);
    }

    for(int t=0;t<=K;t++){
        for(auto e:v[x]){
            if(t+e.cost<=K)down[x][t]+=down[e.to][t+e.cost];

            if(t+e.cost==K){
                for(int s=e.cost-1;s>=0;s--)down[x][t]+=down[e.to][s];
            }
        }
    }

    down[x][K]++;
}

void dfs5(int x,int p,int e){

    if(p!=0){
        for(int t=0;t<=K;t++){
            if(t+e<=K)up[x][t]+=up[p][t+e];

            if(t+e==K){
                for(int s=e-1;s>=0;s--)up[x][t]+=up[p][s];
            }
        }

        for(int t=0;t<=K;t++){
            if(t+e<=K)down[p][t]-=down[x][t+e];

            if(t+e==K){
                for(int s=e-1;s>=0;s--)down[p][t]-=down[x][s];
            }
        }

        down[p][K]--;

        for(int t=0;t<=K;t++){
            if(t+e<=K)up[x][t]+=down[p][t+e];

            if(t+e==K){
                for(int s=e-1;s>=0;s--)up[x][t]+=down[p][s];
            }
        }

        down[p][K]++;

        for(int t=0;t<=K;t++){
            if(t+e<=K)down[p][t]+=down[x][t+e];

            if(t+e==K){
                for(int s=e-1;s>=0;s--)down[p][t]+=down[x][s];
            }
        }
    }

    up[x][K]++;

    for(auto e:v[x]){
        if(e.to==p)continue;
        dfs5(e.to,x,e.cost);
    }

    for(int t=0;t<=K;t++){
        all[x][t]=down[x][t]+up[x][t];
    }
    all[x][K]--;
}

void dfs6(int x,int p){

    cout<<x<<" "<<p<<"\n";

    for(auto e:v[x]){
        if(e.to==p)continue;
        dfs6(e.to,x);
    }

    for(auto e:v[x]){

        long long szz=0;

        if(e.to!=p){
            szz=sz[e.to];

            for(int t=0;t<=K;t++){
                if(t+e.cost<=K)all[x][t]-=down[e.to][t+e.cost];

                if(t+e.cost==K){
                    for(int s=e.cost-1;s>=0;s--)all[x][t]-=down[e.to][s];
                }
            }
        }else{
            szz=n-sz[x];

            for(int t=0;t<=K;t++){
                all[x][t]-=up[x][t];
            }
        }

        for(int f=0;f<e.cost;f++)ans[x]+=all[x][f]*szz;

        if(e.to!=p){
            for(int t=0;t<=K;t++){
                if(t+e.cost<=K)all[x][t]+=down[e.to][t+e.cost];

                if(t+e.cost==K){
                    for(int s=e.cost-1;s>=0;s--)all[x][t]+=down[e.to][s];
                }
            }
        }else{
            for(int t=0;t<=K;t++){
                all[x][t]+=up[x][t];
            }
        }
    }
}

void solve_fast(){

    calc(1,0);
    dfs4(1,0);
    dfs5(1,0,0);
    dfs6(1,0);

    for(int i=1;i<=n;i++){
        cout<<ans[i]<<"\n";
    }
}

int main(){

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin>>n>>K;

    for(int i=1;i<=n-1;i++){
        cin>>a>>b>>c;
        a++; b++;

        v[a].push_back({b,c});
        v[b].push_back({a,c});
    }

    if(n<=1000){
        solve_slow();
    }else if(K<=10){
        solve_fast();
    }else{
        solve_line();
    }

    return 0;
}

• Subtask 0: 0 / 0
• Subtask 1: 18 / 18
• Subtask 2: 0 / 8
• Subtask 3: 0 / 10
• Subtask 4: 0 / 12
• Subtask 5: 0 / 17
• Subtask 6: 0 / 35