Submission #790248

#	Time	Username	Problem	Language	Result	Execution time	Memory
790248		alexander707070	Dungeons Game (IOI21_dungeons)	C++17	37 / 100	7063 ms	129924 KiB

dungeons

#include<bits/stdc++.h>
#define MAXN 400007
using namespace std;

int n,parent[MAXN],to[MAXN],last;
int win[MAXN],lose[MAXN];
vector<int> v[MAXN];
long long curr,dist[MAXN],sum,pref,minloops;

pair<int,int> dp[MAXN][20];
bool li[MAXN][20];

pair<int,int> ff(int x,int p){
    if(x==0)return {n,0};
    if(p==0)return {parent[x],win[parent[x]]};

    if(li[x][p])return dp[x][p];
    li[x][p]=true;

    dp[x][p].first=ff(ff(x,p-1).first,p-1).first;
    dp[x][p].second=max( ff(x,p-1).second , ff(ff(x,p-1).first,p-1).second );
    
    return dp[x][p];
}

void dfs(int x,long long len){
    len+=win[x]; dist[x]=len;
    for(int i=0;i<v[x].size();i++){
        dfs(v[x][i],len);
    }
}

void init(int N,vector<int> s,vector<int> p,vector<int> w,vector<int> l){
    n=N;
    for(int i=0;i<n;i++){
        parent[i]=w[i];
        v[parent[i]].push_back(i);

        to[i]=l[i];

        win[i]=s[i]; lose[i]=p[i];
    }
    parent[n]=n;

    dfs(n,0);
}

vector<int> cycle;
int u[MAXN],tim;

long long simulate(int x, int z){
    curr=z;

    while(x!=n){
        tim++; u[x]=tim;
        while(curr<win[x]){
            curr+=lose[x]; x=to[x];

            if(u[x]==tim)break;
            u[x]=tim;
        }

        if(curr<win[x]){
            cycle.clear(); cycle.push_back(x); sum=lose[x];
            while(to[x]!=cycle[0]){
                cycle.push_back(to[x]); x=to[x];
                sum+=lose[x];
            }
            x=to[x];
            
            minloops=100000000; pref=0;
            for(int i=0;i<cycle.size();i++){
                minloops=min( minloops, int( ceil(1.0*(win[cycle[i]]-curr-pref)/sum) )*1LL );
                pref+=lose[cycle[i]];
            }

            if(minloops<0)minloops=0;
            curr+=minloops*sum;

            int br=0;
            while(curr<win[x]){
                br++;
                if(br>cycle.size())cout<<1/0;
                curr+=lose[x]; x=to[x];
            }
        }

        last=x;
        for(int i=19;i>=0;i--){
            if(ff(x,i).first!=n and ff(x,i).second<=curr){
                x=ff(x,i).first;
            }
        }

        curr+=dist[last]-dist[parent[x]];
        x=parent[x];
    }

    return curr;
}

/*
int main(){
    init(3, {2, 6, 9}, {3, 1, 2}, {2, 2, 3}, {1, 0, 1});
    cout<<simulate(0,1)<<"\n";
    cout<<simulate(2,3)<<"\n";
}
*/

Compilation message (stderr)

dungeons.cpp: In function 'void dfs(int, long long int)':
dungeons.cpp:28:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |     for(int i=0;i<v[x].size();i++){
      |                 ~^~~~~~~~~~~~
dungeons.cpp: In function 'long long int simulate(int, int)':
dungeons.cpp:72:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |             for(int i=0;i<cycle.size();i++){
      |                         ~^~~~~~~~~~~~~
dungeons.cpp:83:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |                 if(br>cycle.size())cout<<1/0;
      |                    ~~^~~~~~~~~~~~~
dungeons.cpp:83:43: warning: division by zero [-Wdiv-by-zero]
   83 |                 if(br>cycle.size())cout<<1/0;
      |                                          ~^~

• Subtask 1: 11 / 11
• Subtask 2: 26 / 26
• Subtask 3: 0 / 13
• Subtask 4: 0 / 12
• Subtask 5: 0 / 27
• Subtask 6: 0 / 11