Submission #1172117

#	Time	Username	Problem	Language	Result	Execution time	Memory
1172117		Ludissey	File Paths (BOI15_fil)	C++20	100 / 100	128 ms	101528 KiB

fil

#include <bits/stdc++.h>
#define int long long
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
 
using namespace std;
vector<vector<int>> child;
vector<vector<int>> achild;
vector<vector<int>> afilechild;
vector<int> depth;
vector<int> a;
vector<int> f;
vector<int> parent;
vector<int> dv;
vector<vector<int>> divs;
int n,m,k,s;
int in=0;
int c=1;
void prep(int x, int d){
    d+=a[x];
    depth[x]=d;
    for (auto u : child[x]) prep(u,d);
}
void dfs(int x){
    if(x>=n-m) return;
    for (auto u : child[x]) dfs(u);
    c++;
    dv[s]=c;
    for (int j=0; j<sz(achild[x]); j++) {
        if(depth[achild[x][j]]-depth[x]+s<=k) dv[depth[achild[x][j]]-depth[x]+s]=c;
    }
    for (int _j=0; _j<sz(afilechild[x]); _j++)
    {
        for (int j=0; j<sz(divs[afilechild[x][_j]]); j++) {
            if(dv[divs[afilechild[x][_j]][j]]==c) {
                f[afilechild[x][_j]]=true; 
                break; 
            }
        }
    }
}

signed main() {
    cin >> n >> m >> k >> s;
    n+=m+1;
    depth.resize(n);
    dv.resize(k+1,0);
    divs.resize(n);
    child.resize(n);
    achild.resize(n);
    afilechild.resize(n);
    f.resize(n);
    a.resize(n);
    parent.resize(n);
    s++;
    for (int i = 1; i < n; i++) {
        int p;
        cin >> p>> a[i]; a[i]++;
        child[p].push_back(i);
        parent[i]=p;
    }
    a[0]=0;
    parent[0]=-1;
    prep(0,0);
    for (int i = n-m; i < n; i++)
    {
        int x=k-depth[i];
        if(x<=0) continue;
        for (int j = 1; j <= sqrt(x); j++)
        {
            if(x%j==0){
                divs[i].push_back(j);
                divs[i].push_back(x/j);
            }
        }
    }
    for (int i = 0; i < n-m; i++){
        int u=i;
        while(u>-1){
            achild[u].push_back(i);
            u=parent[u];
        }
    }
    for (int i = n-m; i < n; i++){
        int u=parent[i];
        while(u>-1){
            afilechild[u].push_back(i);
            u=parent[u];
        }
    }
    dfs(0);
    c++;
    for (int i = 0; i < n-m; i++)
    {
        if(depth[i]+s>k) continue;
        dv[depth[i]+s]=c;
    }
    for (int i = n-m; i < n; i++){
        int u=parent[i];
        if(depth[i]==k||(k-depth[i])%s==0) f[i]=true;
        while(u>-1){
            int x=depth[i]-depth[u];
            int v=k-x;
            if(v>=0&&dv[v]==c) f[i]=true;
            u=parent[u];
        }
    }
    for (int i = n-m; i < n; i++)
    {
        if(f[i]) cout << "YES\n";
        else cout << "NO\n";
    }
    return 0;
}

• Subtask 1: 33 / 33
• Subtask 2: 33 / 33
• Subtask 3: 34 / 34