Submission #94520

#	Time	Username	Problem	Language	Result	Execution time	Memory
94520		nikolapesic2802	Sailing Race (CEOI12_race)	C++14	25 / 100	1173 ms	6776 KiB

race

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>

#define ll long long
#define pb push_back
#define sz(x) (int)(x).size()
#define mp make_pair
#define f first
#define s second
#define all(x) x.begin(), x.end()
#define D(x) cerr << #x << " is " << (x) << "\n";

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;

template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>; ///find_by_order(),order_of_key()
template<class T1, class T2> ostream& operator<<(ostream& os, const pair<T1,T2>& a) { os << '{' << a.f << ", " << a.s << '}'; return os; }
template<class T> ostream& operator<<(ostream& os, const vector<T>& a){os << '{';for(int i=0;i<sz(a);i++){if(i>0&&i<sz(a))os << ", ";os << a[i];}os<<'}';return os;}
template<class T> ostream& operator<<(ostream& os, const set<T>& a) {os << '{';int i=0;for(auto p:a){if(i>0&&i<sz(a))os << ", ";os << p;i++;}os << '}';return os;}
template<class T> ostream& operator<<(ostream& os, const multiset<T>& a) {os << '{';int i=0;for(auto p:a){if(i>0&&i<sz(a))os << ", ";os << p;i++;}os << '}';return os;}
template<class T1,class T2> ostream& operator<<(ostream& os, const map<T1,T2>& a) {os << '{';int i=0;for(auto p:a){if(i>0&&i<sz(a))os << ", ";os << p;i++;}os << '}';return os;}
const int N=501;
bool adj[N][N];
int dp1[N][N][2],dp2[N][N][2],dp3[N][N][2],b[N][2];
pair<int,int> ans;
void calc(int l,int r,int a)
{
    if(adj[l][r])
    {
        dp1[l][r][a]=1;
        dp2[l][r][a]=1+dp3[r][b[l][a]][a^1];
    }
    else
    {
        dp1[l][r][a]=dp2[l][r][a]=INT_MIN;
    }
    for(int k=b[l][a];k!=r;k=b[k][a])
        dp1[l][r][a]=max(dp1[l][r][a],dp1[l][k][a]+dp1[k][r][a]),dp2[l][r][a]=max(dp2[l][r][a],dp1[l][k][a]+dp2[k][r][a]);
    dp3[l][r][a]=max(dp3[l][b[r][a^1]][a],dp2[l][r][a]);
}
int main()
{
	int n,k;
	scanf("%i %i",&n,&k);
	for(int i=0;i<n;i++)
    {
        int t;
        scanf("%i",&t);
        while(t!=0)
        {
            adj[i][t-1]=true;
            scanf("%i",&t);
        }
        b[i][0]=(i+1)%n;
        b[i][1]=(i-1+n)%n;
    }
    for(int l=1;l<n;l++)
        for(int i=0;i<n;i++)
            calc(i,(i+l)%n,0),calc(i,(i-l+n)%n,1);
    for(int i=0;i<n;i++)
        for(int a=0;a<2;a++)
            ans=max(ans,make_pair(dp3[i][b[i][a^1]][a],i));
    if(k)
    {
        for(int i=0;i<n;i++)
            for(int j=0;j<n;j++)
                for(int a=0;a<2;a++)
                    if(dp1[i][j][a]>0)
                    {
                        int k=b[j][a];
                        for(;k!=i;k=b[k][a])
                            if(adj[k][i])
                                break;
                        if(k!=i)
                            for(int l=b[k][a];l!=i;l=b[l][a])
                                if(adj[j][l])
                                    ans=max(ans,make_pair(max(dp3[l][b[i][a^1]][a],dp3[l][b[k][a]][a^1])+dp1[i][j][k]+2,k));
                    }
    }
    printf("%i\n%i\n",ans.first,ans.second+1);
    return 0;
}

Compilation message (stderr)

race.cpp: In function 'int main()':
race.cpp:47:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%i %i",&n,&k);
  ~~~~~^~~~~~~~~~~~~~~
race.cpp:51:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%i",&t);
         ~~~~~^~~~~~~~~
race.cpp:55:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%i",&t);
             ~~~~~^~~~~~~~~

• Subtask 1: 25 / 100