Submission #1018532

# Submission time Handle Problem Language Result Execution time Memory
1018532 2024-07-10T06:33:23 Z MMihalev Sailing Race (CEOI12_race) C++14
95 / 100
1213 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;
                        }
                    }
                }
            }
        }
    }
    if(n>=500)
    {

    }
    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:123:9: warning: unused variable 'prevans' [-Wunused-variable]
  123 |     int prevans=ans;
      |         ^~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 0 ms 604 KB Output is correct
4 Correct 1 ms 2904 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 2904 KB Output is correct
8 Correct 5 ms 3164 KB Output is correct
9 Correct 6 ms 3164 KB Output is correct
10 Correct 6 ms 3164 KB Output is correct
11 Correct 7 ms 3304 KB Output is correct
12 Correct 67 ms 4152 KB Output is correct
13 Correct 174 ms 5396 KB Output is correct
14 Correct 201 ms 6228 KB Output is correct
15 Correct 964 ms 8100 KB Output is correct
16 Incorrect 1146 ms 8100 KB Output isn't correct
17 Correct 926 ms 8016 KB Output is correct
18 Correct 332 ms 8092 KB Output is correct
19 Correct 1213 ms 8096 KB Output is correct
20 Correct 1202 ms 8020 KB Output is correct