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답안 #265339

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
265339 2020-08-14T16:07:02 Z TadijaSebez Sailing Race (CEOI12_race) C++11
100 / 100
 1063 ms 6268 KB 
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
void ckmx(int&x,int y){x=max(x,y);}
const int N=505;
vector<int> E[N];
int dp[N][N][2],n,k,tmp[N];
bool was[N][N][2];
int on(int l,int r,int v){
	return (l<=r&&l<=v&&r>=v)||(l>r&&(v<=r||v>=l));
}
int DP(int l,int r,int side){
	if(was[l][r][side])return dp[l][r][side];
	int u=side==0?l:r;
	was[l][r][side]=1;
	int L=side==0?(l==n?1:l+1):l;
	int R=side==1?(r==1?n:r-1):r;
	for(int v:E[u]){
		if(on(l,r,v)){
			ckmx(dp[l][r][side],1+max(DP(L,v,1),DP(v,R,0)));
		}
	}
	return dp[l][r][side];
}
int go[N][N][2],has[N][N];
int main(){
	scanf("%i %i",&n,&k);
	for(int i=1;i<=n;i++){
		while(1){
			int j;
			scanf("%i",&j);
			if(j==0)break;
			E[i].pb(j);
			has[i][j]=1;
		}
	}
	auto nxt=[&](int x){return x==n?1:x+1;};
	auto pre=[&](int x){return x==1?n:x-1;};
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++)tmp[j]=-N;
		tmp[i]=0;
		for(int j=i;;j=nxt(j)){
			go[i][j][0]=tmp[j];
			for(int r:E[j]){
				ckmx(tmp[r],tmp[j]+1);
			}
			if(j==pre(i))break;
		}
		for(int j=1;j<=n;j++)tmp[j]=-N;
		tmp[i]=0;
		for(int j=i;;j=pre(j)){
			go[i][j][1]=tmp[j];
			for(int r:E[j]){
				ckmx(tmp[r],tmp[j]+1);
			}
			if(j==nxt(i))break;
		}
	}
	int ans=-1,idx=0;
	for(int i=1;i<=n;i++){
		int now=DP(i,i==1?n:i-1,0);
		if(now>ans)ans=now,idx=i;
	}
	if(k==1){
		for(int i=1;i<=n;i++)for(int j=1;j<=n;j++)if(i!=j){
			if(go[i][j][0]!=0){
				int r=-1;
				for(int l=nxt(j);l!=i;l=nxt(l))if(has[l][i]){r=l;break;}
				if(r!=-1){
					for(int z=nxt(r);z!=i;z=nxt(z))if(has[j][z]){
						int now=1+go[i][j][0]+1+max(DP(nxt(r),z,1),DP(z,pre(i),0));
						if(ans<now)ans=now,idx=r;
					}
				}
			}
			if(go[i][j][1]!=0){
				int r=-1;
				for(int l=pre(j);l!=i;l=pre(l))if(has[l][i]){r=l;break;}
				if(r!=-1){
					for(int z=pre(r);z!=i;z=pre(z))if(has[j][z]){
						int now=1+go[i][j][1]+1+max(DP(z,pre(r),0),DP(nxt(i),z,1));
						if(ans<now)ans=now,idx=r;
					}
				}
			}
		}
	}
	printf("%i\n%i\n",ans,idx);
	return 0;
}

Compilation message

race.cpp: In function 'int main()':
race.cpp:27:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |  scanf("%i %i",&n,&k);
      |  ~~~~~^~~~~~~~~~~~~~~
race.cpp:31:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   31 |    scanf("%i",&j);
      |    ~~~~~^~~~~~~~~

Subtask #1
100.0 / 100.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 512 KB Output is correct
3 Correct 1 ms 640 KB Output is correct
4 Correct 2 ms 768 KB Output is correct
5 Correct 2 ms 896 KB Output is correct
6 Correct 3 ms 1056 KB Output is correct
7 Correct 6 ms 1152 KB Output is correct
8 Correct 5 ms 1280 KB Output is correct
9 Correct 10 ms 1408 KB Output is correct
10 Correct 22 ms 1536 KB Output is correct
11 Correct 11 ms 1536 KB Output is correct
12 Correct 64 ms 2552 KB Output is correct
13 Correct 139 ms 3728 KB Output is correct
14 Correct 95 ms 4832 KB Output is correct
15 Correct 735 ms 6092 KB Output is correct
16 Correct 928 ms 6220 KB Output is correct
17 Correct 753 ms 6092 KB Output is correct
18 Correct 115 ms 5880 KB Output is correct
19 Correct 1055 ms 6268 KB Output is correct
20 Correct 1063 ms 6268 KB Output is correct