Submission #1018537

# Submission time Handle Problem Language Result Execution time Memory
1018537 2024-07-10T06:34:51 Z MMihalev Sailing Race (CEOI12_race) C++14
95 / 100
1264 ms 8100 KB
#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
const int MAX_N=6e2+10;
//0 clockwise
//1 counterclockwise
vector<int>track[MAX_N][2];//0 - ; 1 +
int n;
bool edge[MAX_N][MAX_N];
int type;
int dp[MAX_N][MAX_N][2];
int dist[MAX_N][MAX_N][2];//0 - ; 1 +
void precompute()
{
    for(int i=1;i<=n;i++)
    {
        for(int j=i+1;j<=n;j++)
        {
            track[i][0].push_back(j);
        }
        for(int j=1;j<i;j++)
        {
            track[i][0].push_back(j);
        }
        //0

        for(int j=i-1;j>=1;j--)
        {
            track[i][1].push_back(j);
        }
        for(int j=n;j>i;j--)
        {
            track[i][1].push_back(j);
        }
        //1
    }
    ///track


    for(int u=1;u<=n;u++)
    {
        for(int j=0;j<n-1;j++)
        {
            int v=track[u][0][j];
            dist[u][v][0]=1e9;
            for(int r=0;r<j;r++)
            {
                int prev=track[u][0][r];
                if(edge[prev][v] && dist[u][prev][0]!=1e9)
                {
                    dist[u][v][0]=min(dist[u][v][0],dist[u][prev][0]+1);
                }
            }
            if(edge[u][v])dist[u][v][0]=1;
        }
        //0

        for(int j=0;j<n-1;j++)
        {
            int v=track[u][1][j];
            dist[u][v][1]=1e9;
            for(int r=0;r<j;r++)
            {
                int prev=track[u][1][r];
                if(edge[prev][v] && dist[u][prev][1]!=1e9)
                {
                    dist[u][v][1]=min(dist[u][v][1],dist[u][prev][1]+1);
                }
            }
            if(edge[u][v])dist[u][v][1]=1;
        }
        //1
    }
    ///dist

    for(int used=1;used<n;used++)
    {
        for(int dir=0;dir<2;dir++)
        {
            for(int u=1;u<=n;u++)
            {
                dp[u][used][dir]=dp[u][used-1][dir];
                for(int i=0;i<used;i++)
                {
                    int v=track[u][dir][i];
                    int pref=i;
                    int suf=used-1-i;

                    if(edge[u][v])dp[u][used][dir]=max(dp[u][used][dir],max(dp[v][suf][dir],dp[v][pref][1-dir])+1);
                }
            }
        }
    }
    ///dp
}
void read()
{
    cin>>n>>type;
    for(int u=1;u<=n;u++)
    {
        int v;
        cin>>v;
        while(v!=0)
        {
            edge[u][v]=1;
            cin>>v;
        }
    }
}
void solve()
{
    int ans=-1;
    int idx=-1;

    for(int u=1;u<=n;u++)
    {
        if(max(dp[u][n-1][0],dp[u][n-1][1])>=ans)
        {
            ans=max(dp[u][n-1][0],dp[u][n-1][1]);
            idx=u;
        }
    }

    int prevans=ans;

    if(type==1)
    {
        for(int dir=0;dir<2;dir++)
        {
            for(int T=1;T<=n;T++)
            {
                for(int i=0;i<n-1;i++)
                {
                    int Y=track[T][dir][i];
                    int S=-10;
                    int idS=-1;
                    for(int j=i-1;j>=0;j--)
                    {
                        int X=track[T][dir][j];
                        if(S!=-10 && dist[T][X][dir]!=1e9 && edge[X][Y])
                        {
                            int currer=1+dist[T][X][dir]+1+max(dp[Y][n-2-i][dir],dp[Y][i-idS-1][1-dir]);
                            if(currer>ans)
                            {
                                ans=currer;
                                idx=S;
                            }
                        }
                        if(edge[X][T])
                        {
                            S=X;
                            idS=j;
                        }
                    }
                }
            }
        }
    }

    cout<<ans<<"\n";
    cout<<idx<<"\n";
}
int main ()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    read();
    precompute();
    solve();
    return 0;
}

Compilation message

race.cpp: In function 'void solve()':
race.cpp:125:9: warning: unused variable 'prevans' [-Wunused-variable]
  125 |     int prevans=ans;
      |         ^~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 600 KB Output is correct
2 Correct 0 ms 604 KB Output is correct
3 Correct 1 ms 604 KB Output is correct
4 Correct 2 ms 2908 KB Output is correct
5 Correct 1 ms 2908 KB Output is correct
6 Correct 3 ms 2908 KB Output is correct
7 Correct 3 ms 3132 KB Output is correct
8 Correct 5 ms 3164 KB Output is correct
9 Correct 5 ms 3164 KB Output is correct
10 Correct 5 ms 3164 KB Output is correct
11 Correct 8 ms 3160 KB Output is correct
12 Correct 65 ms 4188 KB Output is correct
13 Correct 168 ms 5392 KB Output is correct
14 Correct 195 ms 6228 KB Output is correct
15 Correct 971 ms 8100 KB Output is correct
16 Incorrect 1047 ms 8092 KB Output isn't correct
17 Correct 942 ms 8092 KB Output is correct
18 Correct 342 ms 8092 KB Output is correct
19 Correct 1193 ms 8092 KB Output is correct
20 Correct 1264 ms 8016 KB Output is correct