oj.uz

Submission #235205

# Submission time Handle Problem Language Result Execution time Memory
235205 2020-05-27T10:52:18 Z AMO5 Building 4 (JOI20_building4) C++
100 / 100
 321 ms 44908 KB 
#include <bits/stdc++.h>
 
using namespace std;
 
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(x) (x).begin(), (x).end() 
#define MOD 1000000007
 
typedef long long ll;
typedef pair <int, int> ii;
typedef pair <ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef long double ld;
 
ll INF=LLONG_MAX;
 
int const mxn = 1e6+5;
int dp[mxn][2][2]; //pos, cur, min/max = cnt of b;
int a[mxn],b[mxn];

void mins(int &a, int b){
	a = min(a,b);
	return;
}

void maxs(int &a, int b){
	a = max(a,b);
	return;
}
 
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0);
    //freopen("input.txt","r",stdin); freopen("output.txt","w",stdout);
	int n; cin >> n;
	memset(dp,-1,sizeof(dp));
	for(int i=1; i<=n*2; i++)cin >> a[i];
	for(int i=1; i<=n*2; i++)cin >> b[i];
	dp[1][0][0] = dp[1][0][1] = 0;
	dp[1][1][0] = dp[1][1][1] = 1;
	for(int i=2; i<=n*2; i++){
		dp[i][0][0]=dp[i][1][0] = mxn;
		dp[i][0][1]=dp[i][1][1] = -1;
		if(a[i]>=a[i-1]){
			mins(dp[i][0][0],dp[i-1][0][0]);
			maxs(dp[i][0][1],dp[i-1][0][1]);
		}
		if(a[i]>=b[i-1]){
			mins(dp[i][0][0],dp[i-1][1][0]);
			maxs(dp[i][0][1],dp[i-1][1][1]);
		}
		if(b[i]>=a[i-1]){
			mins(dp[i][1][0],dp[i-1][0][0]+1);
			maxs(dp[i][1][1],dp[i-1][0][1]+1);
		}
		if(b[i]>=b[i-1]){
			mins(dp[i][1][0],dp[i-1][1][0]+1);
			maxs(dp[i][1][1],dp[i-1][1][1]+1);
		}
	}
	bool cur=0; int cnt=n;
	if(dp[n*2][0][0]<=n&&n<=dp[n*2][0][1])cur = 0;
	else if(dp[n*2][1][0]<=n&&n<=dp[n*2][1][1])cur = 1;
	else{
		cout << -1 << endl;
		return 0;
	}
	//start backtracking
	string s="";
	for(int i=n*2; i>=1; i--){
		if(!cur){
			s+='A';
			if(a[i-1]<=a[i]&&dp[i-1][0][0]<=cnt&&cnt<=dp[i-1][0][1])cur = 0;
			if(b[i-1]<=a[i]&&dp[i-1][1][0]<=cnt&&cnt<=dp[i-1][1][1])cur = 1; 
		}else{
			s+='B';
			cnt--;
			if(a[i-1]<=b[i]&&dp[i-1][0][0]<=cnt&&cnt<=dp[i-1][0][1])cur = 0;
			if(b[i-1]<=b[i]&&dp[i-1][1][0]<=cnt&&cnt<=dp[i-1][1][1])cur = 1; 
		}
	}
	reverse(all(s));
	cout << s << endl;
}

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 16000 KB Output is correct
2 Correct 12 ms 16000 KB Output is correct
3 Correct 13 ms 15872 KB Output is correct
4 Correct 13 ms 16000 KB Output is correct
5 Correct 14 ms 16256 KB Output is correct
6 Correct 13 ms 16128 KB Output is correct
7 Correct 14 ms 16128 KB Output is correct
8 Correct 14 ms 16128 KB Output is correct
9 Correct 14 ms 16128 KB Output is correct
10 Correct 13 ms 16128 KB Output is correct
11 Correct 14 ms 16128 KB Output is correct
12 Correct 14 ms 16128 KB Output is correct
13 Correct 14 ms 16128 KB Output is correct
14 Correct 16 ms 16128 KB Output is correct
15 Correct 14 ms 16128 KB Output is correct
16 Correct 14 ms 16128 KB Output is correct
17 Correct 14 ms 16128 KB Output is correct
18 Correct 14 ms 16128 KB Output is correct
19 Correct 14 ms 16128 KB Output is correct
20 Correct 13 ms 16128 KB Output is correct
21 Correct 14 ms 16128 KB Output is correct
22 Correct 14 ms 16128 KB Output is correct
23 Correct 13 ms 16128 KB Output is correct
24 Correct 13 ms 16128 KB Output is correct
25 Correct 13 ms 16128 KB Output is correct
26 Correct 12 ms 16128 KB Output is correct
27 Correct 15 ms 16128 KB Output is correct
28 Correct 13 ms 16128 KB Output is correct
29 Correct 13 ms 16128 KB Output is correct
30 Correct 14 ms 16104 KB Output is correct
31 Correct 13 ms 16128 KB Output is correct
32 Correct 13 ms 16128 KB Output is correct
33 Correct 13 ms 16128 KB Output is correct

Subtask #2
89.0 / 89.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 16000 KB Output is correct
2 Correct 12 ms 16000 KB Output is correct
3 Correct 13 ms 15872 KB Output is correct
4 Correct 13 ms 16000 KB Output is correct
5 Correct 14 ms 16256 KB Output is correct
6 Correct 13 ms 16128 KB Output is correct
7 Correct 14 ms 16128 KB Output is correct
8 Correct 14 ms 16128 KB Output is correct
9 Correct 14 ms 16128 KB Output is correct
10 Correct 13 ms 16128 KB Output is correct
11 Correct 14 ms 16128 KB Output is correct
12 Correct 14 ms 16128 KB Output is correct
13 Correct 14 ms 16128 KB Output is correct
14 Correct 16 ms 16128 KB Output is correct
15 Correct 14 ms 16128 KB Output is correct
16 Correct 14 ms 16128 KB Output is correct
17 Correct 14 ms 16128 KB Output is correct
18 Correct 14 ms 16128 KB Output is correct
19 Correct 14 ms 16128 KB Output is correct
20 Correct 13 ms 16128 KB Output is correct
21 Correct 14 ms 16128 KB Output is correct
22 Correct 14 ms 16128 KB Output is correct
23 Correct 13 ms 16128 KB Output is correct
24 Correct 13 ms 16128 KB Output is correct
25 Correct 13 ms 16128 KB Output is correct
26 Correct 12 ms 16128 KB Output is correct
27 Correct 15 ms 16128 KB Output is correct
28 Correct 13 ms 16128 KB Output is correct
29 Correct 13 ms 16128 KB Output is correct
30 Correct 14 ms 16104 KB Output is correct
31 Correct 13 ms 16128 KB Output is correct
32 Correct 13 ms 16128 KB Output is correct
33 Correct 13 ms 16128 KB Output is correct
34 Correct 290 ms 41900 KB Output is correct
35 Correct 292 ms 43160 KB Output is correct
36 Correct 284 ms 42672 KB Output is correct
37 Correct 308 ms 43312 KB Output is correct
38 Correct 294 ms 42928 KB Output is correct
39 Correct 277 ms 42416 KB Output is correct
40 Correct 304 ms 44908 KB Output is correct
41 Correct 279 ms 43312 KB Output is correct
42 Correct 300 ms 44336 KB Output is correct
43 Correct 311 ms 37744 KB Output is correct
44 Correct 321 ms 37872 KB Output is correct
45 Correct 312 ms 37740 KB Output is correct
46 Correct 296 ms 37612 KB Output is correct
47 Correct 295 ms 44392 KB Output is correct
48 Correct 285 ms 44140 KB Output is correct
49 Correct 292 ms 43372 KB Output is correct
50 Correct 297 ms 44396 KB Output is correct
51 Correct 312 ms 44396 KB Output is correct
52 Correct 183 ms 33612 KB Output is correct
53 Correct 184 ms 33496 KB Output is correct
54 Correct 172 ms 33644 KB Output is correct
55 Correct 173 ms 33260 KB Output is correct
56 Correct 304 ms 31340 KB Output is correct
57 Correct 255 ms 40428 KB Output is correct
58 Correct 255 ms 40556 KB Output is correct
59 Correct 258 ms 40556 KB Output is correct
60 Correct 243 ms 39344 KB Output is correct
61 Correct 266 ms 41240 KB Output is correct
62 Correct 267 ms 40684 KB Output is correct
63 Correct 265 ms 41196 KB Output is correct
64 Correct 254 ms 40112 KB Output is correct
65 Correct 265 ms 41068 KB Output is correct