oj.uz

Submission #211788

# Submission time Handle Problem Language Result Execution time Memory
211788 2020-03-21T09:20:02 Z zscoder Building 4 (JOI20_building4) C++17
100 / 100
 328 ms 44780 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;
 
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define fbo find_by_order
#define ook order_of_key
 
typedef long long ll;
typedef pair<int,int> ii;
typedef vector<int> vi;
typedef long double ld; 
typedef tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> pbds;

const int N = 1055555;
int a[2][N+1];
ii dp[N+1][2];

//int dp[5555][5555];

void uni(ii &a, ii b)
{
	a.fi=min(a.fi,b.fi);
	a.se=max(a.se,b.se);
}

int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	int n; cin>>n; n*=2;
	const bool DEBUG = 0;
	for(int cc=1;;cc++)
	{
		if(!DEBUG)
		{
			for(int i=0;i<n;i++)
			{
				cin>>a[0][i];
			}
			for(int i=0;i<n;i++)
			{
				cin>>a[1][i];
			}
		}
		else
		{
			for(int i=0;i<n;i++)
			{
				a[0][i]=rand();
				a[1][i]=rand();
			}
		}
		/*
		for(int i=0;i<n;i++)
		{
			for(int j=0;j<=n;j++)
			{
				dp[i][j]=int(1e9)+7;
			}
		}
		dp[0][1]=a[0][0];
		dp[0][0]=a[1][0];
		for(int i=1;i<n;i++)
		{
			for(int j=0;j<=i+1;j++)
			{
				//choose a
				if(j&&dp[i-1][j-1]<=a[0][i]) dp[i][j]=min(dp[i][j],a[0][i]);
				if(dp[i-1][j]<=a[1][i]) dp[i][j]=min(dp[i][j],a[1][i]);
			}
			int l=int(1e9);
			int r=0;
			int cnt=0;
			for(int j=0;j<=i+1;j++)
			{
				if(dp[i][j]<int(1e9)+7)
				{
					l=min(l,j); r=max(r,j); cnt++;
				}
			}
			if(l>r) l=r+1;
			assert(cnt==r-l+1);
		}
		*/
		dp[0][0]={0,0};
		dp[0][1]={1,1};
		for(int i=1;i<n;i++)
		{
			for(int j=0;j<2;j++)
			{
				dp[i][j]={int(1e9),-int(1e9)};
				//use a[j][i]
				for(int k=0;k<2;k++)
				{
					if(dp[i-1][k].fi>dp[i-1][k].se) continue;
					if(a[k][i-1]<=a[j][i]) uni(dp[i][j],{dp[i-1][k].fi+j,dp[i-1][k].se+j});
				}
				//cerr<<i<<' '<<j<<' '<<dp[i][j].fi<<' '<<dp[i][j].se<<'\n';
			}
		}
		int endpos=-1;
		for(int i=0;i<2;i++)
		{
			if(dp[n-1][i].fi<=n/2&&dp[n-1][i].se>=n/2)
			{
				endpos=i; break;
			}
		}
		if(endpos==-1)
		{
			cout<<endpos<<'\n';
		}
		else
		{
			string s;
			int cnt=n/2;
			for(int i=n-1;i>=0;i--)
			{
				s+=char('A'+endpos);
				cnt-=endpos;
				if(i>0)
				{
					//look at dp[endpos][i]
					int pos=0;
					for(int j=0;j<2;j++)
					{
						if(dp[i-1][j].fi<=cnt&&cnt<=dp[i-1][j].se&&a[j][i-1]<=a[endpos][i])
						{
							endpos=j; pos=1;
							break;
						}
					}
					assert(pos);
				}
			}
			reverse(s.begin(),s.end());
			cout<<s<<'\n';
		}
		if(DEBUG)
		{
			cerr<<"Case #"<<cc<<" completed\n";
		}
		else return 0;
	}
}

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 5 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 6 ms 512 KB Output is correct
6 Correct 6 ms 512 KB Output is correct
7 Correct 6 ms 512 KB Output is correct
8 Correct 6 ms 560 KB Output is correct
9 Correct 6 ms 512 KB Output is correct
10 Correct 6 ms 512 KB Output is correct
11 Correct 6 ms 512 KB Output is correct
12 Correct 6 ms 512 KB Output is correct
13 Correct 6 ms 512 KB Output is correct
14 Correct 6 ms 512 KB Output is correct
15 Correct 6 ms 512 KB Output is correct
16 Correct 6 ms 512 KB Output is correct
17 Correct 6 ms 512 KB Output is correct
18 Correct 6 ms 640 KB Output is correct
19 Correct 6 ms 512 KB Output is correct
20 Correct 5 ms 512 KB Output is correct
21 Correct 5 ms 512 KB Output is correct
22 Correct 5 ms 512 KB Output is correct
23 Correct 5 ms 512 KB Output is correct
24 Correct 6 ms 512 KB Output is correct
25 Correct 6 ms 512 KB Output is correct
26 Correct 5 ms 512 KB Output is correct
27 Correct 6 ms 512 KB Output is correct
28 Correct 5 ms 512 KB Output is correct
29 Correct 6 ms 512 KB Output is correct
30 Correct 5 ms 512 KB Output is correct
31 Correct 6 ms 512 KB Output is correct
32 Correct 5 ms 512 KB Output is correct
33 Correct 6 ms 512 KB Output is correct

Subtask #2
89.0 / 89.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 5 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 6 ms 512 KB Output is correct
6 Correct 6 ms 512 KB Output is correct
7 Correct 6 ms 512 KB Output is correct
8 Correct 6 ms 560 KB Output is correct
9 Correct 6 ms 512 KB Output is correct
10 Correct 6 ms 512 KB Output is correct
11 Correct 6 ms 512 KB Output is correct
12 Correct 6 ms 512 KB Output is correct
13 Correct 6 ms 512 KB Output is correct
14 Correct 6 ms 512 KB Output is correct
15 Correct 6 ms 512 KB Output is correct
16 Correct 6 ms 512 KB Output is correct
17 Correct 6 ms 512 KB Output is correct
18 Correct 6 ms 640 KB Output is correct
19 Correct 6 ms 512 KB Output is correct
20 Correct 5 ms 512 KB Output is correct
21 Correct 5 ms 512 KB Output is correct
22 Correct 5 ms 512 KB Output is correct
23 Correct 5 ms 512 KB Output is correct
24 Correct 6 ms 512 KB Output is correct
25 Correct 6 ms 512 KB Output is correct
26 Correct 5 ms 512 KB Output is correct
27 Correct 6 ms 512 KB Output is correct
28 Correct 5 ms 512 KB Output is correct
29 Correct 6 ms 512 KB Output is correct
30 Correct 5 ms 512 KB Output is correct
31 Correct 6 ms 512 KB Output is correct
32 Correct 5 ms 512 KB Output is correct
33 Correct 6 ms 512 KB Output is correct
34 Correct 309 ms 42448 KB Output is correct
35 Correct 299 ms 25592 KB Output is correct
36 Correct 294 ms 24496 KB Output is correct
37 Correct 306 ms 28720 KB Output is correct
38 Correct 296 ms 29476 KB Output is correct
39 Correct 285 ms 26032 KB Output is correct
40 Correct 310 ms 44780 KB Output is correct
41 Correct 281 ms 25648 KB Output is correct
42 Correct 324 ms 43760 KB Output is correct
43 Correct 309 ms 38764 KB Output is correct
44 Correct 328 ms 39532 KB Output is correct
45 Correct 315 ms 41836 KB Output is correct
46 Correct 311 ms 38508 KB Output is correct
47 Correct 315 ms 26976 KB Output is correct
48 Correct 296 ms 43884 KB Output is correct
49 Correct 326 ms 40556 KB Output is correct
50 Correct 320 ms 44452 KB Output is correct
51 Correct 323 ms 44520 KB Output is correct
52 Correct 190 ms 33516 KB Output is correct
53 Correct 186 ms 33644 KB Output is correct
54 Correct 172 ms 33724 KB Output is correct
55 Correct 179 ms 33260 KB Output is correct
56 Correct 306 ms 41324 KB Output is correct
57 Correct 281 ms 40432 KB Output is correct
58 Correct 284 ms 40532 KB Output is correct
59 Correct 276 ms 40556 KB Output is correct
60 Correct 257 ms 38448 KB Output is correct
61 Correct 283 ms 40844 KB Output is correct
62 Correct 278 ms 40552 KB Output is correct
63 Correct 273 ms 40712 KB Output is correct
64 Correct 263 ms 39468 KB Output is correct
65 Correct 270 ms 40684 KB Output is correct