oj.uz

Submission #920639

# Submission time Handle Problem Language Result Execution time Memory
920639 2024-02-02T20:05:10 Z alexander707070 Building 4 (JOI20_building4) C++14
11 / 100
 381 ms 137952 KB 
#include<bits/stdc++.h>
#define MAXN 1000007
using namespace std;

const int inf=1e9;

int n,a[MAXN],b[MAXN],cnt,p[MAXN],l,r;
int dp[MAXN][2],dp2[MAXN][2];
bool li[MAXN][2],li2[MAXN][2];

queue<int> s;

string sol,sol2;

int ff(int pos,int last){
	if(pos==n+1)return 0;

	if(li[pos][last])return dp[pos][last];
	li[pos][last]=true;
	dp[pos][last]=-inf;

	int x=0;
	if(last==0)x=a[pos-1];
	else x=b[pos-1];

	if(a[pos]>=x){
		dp[pos][last]=max(dp[pos][last],ff(pos+1,0)+1);
	}

	if(b[pos]>=x){
		dp[pos][last]=max(dp[pos][last],ff(pos+1,1));
	}

	return dp[pos][last];
}

int ff2(int pos,int last){
	if(pos==n+1)return 0;

	if(li2[pos][last])return dp2[pos][last];
	li2[pos][last]=true;
	dp2[pos][last]=-inf;

	int x=0;
	if(last==0)x=a[pos-1];
	else x=b[pos-1];

	if(a[pos]>=x){
		dp2[pos][last]=max(dp2[pos][last],ff2(pos+1,0));
	}

	if(b[pos]>=x){
		dp2[pos][last]=max(dp2[pos][last],ff2(pos+1,1)+1);
	}

	return dp2[pos][last];
}

void solve(int pos,int last){
	if(pos==n+1)return;

	int x;
	if(last==0)x=a[pos-1];
	else x=b[pos-1];

	if(a[pos]>=x and ff(pos,last)==ff(pos+1,0)+1){
		sol+="A"; solve(pos+1,0); return;
	}else{
		sol+="B"; solve(pos+1,1); return;
	}
}

void solve2(int pos,int last){
	if(pos==n+1)return;

	int x;
	if(last==0)x=a[pos-1];
	else x=b[pos-1];

	if(b[pos]>=x and ff2(pos,last)==ff2(pos+1,1)+1){
		sol2+="B"; solve2(pos+1,1); return;
	}else{
		sol2+="A"; solve2(pos+1,0); return;
	}
}

bool vis[MAXN];

void bfs(int pos){

	if(pos>0 and !vis[pos-1] and sol[pos-1]=='A' and sol2[pos-1]=='B'){
		l=pos-1;
		if(b[l+1]>=p[l] and b[l+1]<=p[l+2]){
			s.push(pos-1);
			vis[pos-1]=true;
		}
	}

	if(pos<n-1 and !vis[pos+1] and sol[pos+1]=='A' and sol2[pos+1]=='B'){
		l=pos+1;
		if(b[l+1]>=p[l] and b[l+1]<=p[l+2]){
			s.push(pos+1);
			vis[pos+1]=true;
		}
	}
}

int main(){

	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);

	cin>>n;
	n*=2;
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	for(int i=1;i<=n;i++){
		cin>>b[i];
	}

	if(ff(1,0)<0 or ff(1,0)<n/2 or ff2(1,0)<n/2){
		cout<<"-1\n";
		return 0;
	}

	cnt=ff(1,0);
	solve(1,0); solve2(1,0);

	for(int i=0;i<sol.size();i++){
		if(sol[i]=='A')p[i+1]=a[i+1];
		else p[i+1]=b[i+1];
	}
	p[n+1]=inf;

	for(int t=0;t<10;t++){

	for(int i=0;i<sol.size();i++){
		if(sol[i]=='A' and sol2[i]=='B'){
			if(b[i+1]>=p[i] and b[i+1]<=p[i+2]){
				s.push(i); vis[i]=true;
			}
		}
	}

	while(cnt>n/2 and !s.empty()){
		sol[s.front()]='B'; 
		p[s.front()+1]=b[s.front()+1];

		bfs(s.front());
		s.pop();

		cnt--;
	}

	}

	if(cnt>n/2){
		for(int i=0;i<sol.size();i++){
			if(sol[i]=='A' and p[i+1]!=a[i+1])cout<<1/0;
			if(sol[i]=='B' and p[i+1]!=b[i+1])cout<<1/0;
		}
		
		return 0;
	}

	cout<<sol<<"\n";
	

	return 0;
}

Compilation message

building4.cpp: In function 'int main()':
building4.cpp:131:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  131 |  for(int i=0;i<sol.size();i++){
      |              ~^~~~~~~~~~~
building4.cpp:139:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  139 |  for(int i=0;i<sol.size();i++){
      |              ~^~~~~~~~~~~
building4.cpp:160:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  160 |   for(int i=0;i<sol.size();i++){
      |               ~^~~~~~~~~~~
building4.cpp:161:45: warning: division by zero [-Wdiv-by-zero]
  161 |    if(sol[i]=='A' and p[i+1]!=a[i+1])cout<<1/0;
      |                                            ~^~
building4.cpp:162:45: warning: division by zero [-Wdiv-by-zero]
  162 |    if(sol[i]=='B' and p[i+1]!=b[i+1])cout<<1/0;
      |                                            ~^~

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12632 KB Output is correct
2 Correct 1 ms 8536 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12636 KB Output is correct
5 Correct 2 ms 8540 KB Output is correct
6 Correct 3 ms 13024 KB Output is correct
7 Correct 3 ms 12892 KB Output is correct
8 Correct 3 ms 13068 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 2 ms 13024 KB Output is correct
11 Correct 3 ms 13088 KB Output is correct
12 Correct 3 ms 12892 KB Output is correct
13 Correct 3 ms 12888 KB Output is correct
14 Correct 3 ms 13148 KB Output is correct
15 Correct 3 ms 13144 KB Output is correct
16 Correct 3 ms 10844 KB Output is correct
17 Correct 3 ms 13144 KB Output is correct
18 Correct 3 ms 12892 KB Output is correct
19 Correct 3 ms 12892 KB Output is correct
20 Correct 3 ms 12892 KB Output is correct
21 Correct 3 ms 12892 KB Output is correct
22 Correct 4 ms 13148 KB Output is correct
23 Correct 3 ms 13056 KB Output is correct
24 Correct 3 ms 12892 KB Output is correct
25 Correct 2 ms 12892 KB Output is correct
26 Correct 3 ms 12892 KB Output is correct
27 Correct 3 ms 12892 KB Output is correct
28 Correct 3 ms 12896 KB Output is correct
29 Correct 3 ms 12888 KB Output is correct
30 Correct 3 ms 12892 KB Output is correct
31 Correct 3 ms 12892 KB Output is correct
32 Correct 3 ms 13028 KB Output is correct
33 Correct 3 ms 12892 KB Output is correct

Subtask #2
0 / 89.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 12632 KB Output is correct
2 Correct 1 ms 8536 KB Output is correct
3 Correct 2 ms 12636 KB Output is correct
4 Correct 2 ms 12636 KB Output is correct
5 Correct 2 ms 8540 KB Output is correct
6 Correct 3 ms 13024 KB Output is correct
7 Correct 3 ms 12892 KB Output is correct
8 Correct 3 ms 13068 KB Output is correct
9 Correct 3 ms 12892 KB Output is correct
10 Correct 2 ms 13024 KB Output is correct
11 Correct 3 ms 13088 KB Output is correct
12 Correct 3 ms 12892 KB Output is correct
13 Correct 3 ms 12888 KB Output is correct
14 Correct 3 ms 13148 KB Output is correct
15 Correct 3 ms 13144 KB Output is correct
16 Correct 3 ms 10844 KB Output is correct
17 Correct 3 ms 13144 KB Output is correct
18 Correct 3 ms 12892 KB Output is correct
19 Correct 3 ms 12892 KB Output is correct
20 Correct 3 ms 12892 KB Output is correct
21 Correct 3 ms 12892 KB Output is correct
22 Correct 4 ms 13148 KB Output is correct
23 Correct 3 ms 13056 KB Output is correct
24 Correct 3 ms 12892 KB Output is correct
25 Correct 2 ms 12892 KB Output is correct
26 Correct 3 ms 12892 KB Output is correct
27 Correct 3 ms 12892 KB Output is correct
28 Correct 3 ms 12896 KB Output is correct
29 Correct 3 ms 12888 KB Output is correct
30 Correct 3 ms 12892 KB Output is correct
31 Correct 3 ms 12892 KB Output is correct
32 Correct 3 ms 13028 KB Output is correct
33 Correct 3 ms 12892 KB Output is correct
34 Correct 151 ms 32868 KB Output is correct
35 Correct 307 ms 110804 KB Output is correct
36 Correct 307 ms 109260 KB Output is correct
37 Correct 314 ms 111192 KB Output is correct
38 Correct 290 ms 129924 KB Output is correct
39 Correct 277 ms 120084 KB Output is correct
40 Correct 292 ms 120112 KB Output is correct
41 Correct 306 ms 112340 KB Output is correct
42 Correct 335 ms 114492 KB Output is correct
43 Correct 329 ms 117524 KB Output is correct
44 Correct 323 ms 117576 KB Output is correct
45 Correct 335 ms 117576 KB Output is correct
46 Correct 318 ms 137952 KB Output is correct
47 Correct 324 ms 126812 KB Output is correct
48 Correct 291 ms 126668 KB Output is correct
49 Correct 332 ms 127044 KB Output is correct
50 Correct 330 ms 116532 KB Output is correct
51 Correct 333 ms 116552 KB Output is correct
52 Correct 288 ms 105664 KB Output is correct
53 Correct 300 ms 105800 KB Output is correct
54 Correct 381 ms 118544 KB Output is correct
55 Correct 263 ms 126032 KB Output is correct
56 Correct 330 ms 117832 KB Output is correct
57 Correct 282 ms 112356 KB Output is correct
58 Correct 280 ms 112960 KB Output is correct
59 Correct 279 ms 112812 KB Output is correct
60 Correct 240 ms 107984 KB Output is correct
61 Correct 256 ms 113228 KB Output is correct
62 Incorrect 250 ms 111116 KB Unexpected end of file - token expected
63 Halted 0 ms 0 KB -