oj.uz

Submission #211737

# Submission time Handle Problem Language Result Execution time Memory
211737 2020-03-21T06:03:31 Z nibnalin Building 4 (JOI20_building4) C++17
11 / 100
 96 ms 8576 KB 
#include <iostream>
#include <cstdio>
#include <vector>
using namespace std;

const int maxn = int(5e5)+5, inf = int(1e9)+5;

int n, A[maxn], B[maxn];
pair<int, int> memo[maxn][2];

pair<int, int> DP(int idx, int prev)
{
	if(idx > 2*n) return {0, 0};
	else if(memo[idx][prev].first != -1) return memo[idx][prev];
	else
	{
		int p = prev?B[idx-1]:A[idx-1];
		pair<int, int> res = {inf, -inf}, tmp;
		if(A[idx] >= p)
		{
			tmp = DP(idx+1, 0);
			res.first = min(res.first, tmp.first+1);
			res.second = max(res.second, tmp.second+1);
		}
		if(B[idx] >= p)
		{
			tmp = DP(idx+1, 1);
			res.first = min(res.first, tmp.first);
			res.second = max(res.second, tmp.second);
		}

		return memo[idx][prev] = res;
	}
}

int main(void)
{
	scanf("%d", &n);
	for(int i = 1;i <= 2*n;i++) scanf("%d", &A[i]);
	for(int i = 1;i <= 2*n;i++) scanf("%d", &B[i]);

	for(int i = 0;i < maxn;i++) memo[i][0] = memo[i][1] = {-1, -1};

	pair<int, int> res = DP(1, 0);
	if(!(res.first <= n && n <= res.second))
	{
		printf("-1\n");
		return 0;
	}

	int cur = 0, idx = 1, prev = 0;

	while(idx <= 2*n)
	{
		int p = prev?B[idx-1]:A[idx-1];
		pair<int, int> tmp;
		if(A[idx] >= p)
		{
			tmp = DP(idx+1, 0);
			if(tmp.first+1 <= n-cur && n-cur <= tmp.second+1)
			{
				printf("A");
				prev = 0;
				idx++, cur++;
				continue;
			}
		}
		if(B[idx] >= p)
		{
			tmp = DP(idx+1, 1);
			if(tmp.first <= n-cur && n-cur <= tmp.second)
			{
				printf("B");
				prev = 1;
				idx++;
				continue;
			}
		}
	}
	printf("\n");
}

Compilation message

building4.cpp: In function 'int main()':
building4.cpp:38:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
  ~~~~~^~~~~~~~~~
building4.cpp:39:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i = 1;i <= 2*n;i++) scanf("%d", &A[i]);
                              ~~~~~^~~~~~~~~~~~~
building4.cpp:40:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i = 1;i <= 2*n;i++) scanf("%d", &B[i]);
                              ~~~~~^~~~~~~~~~~~~

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 8192 KB Output is correct
2 Correct 8 ms 8192 KB Output is correct
3 Correct 8 ms 8192 KB Output is correct
4 Correct 9 ms 8192 KB Output is correct
5 Correct 10 ms 8320 KB Output is correct
6 Correct 10 ms 8448 KB Output is correct
7 Correct 10 ms 8448 KB Output is correct
8 Correct 10 ms 8448 KB Output is correct
9 Correct 10 ms 8448 KB Output is correct
10 Correct 10 ms 8448 KB Output is correct
11 Correct 10 ms 8576 KB Output is correct
12 Correct 10 ms 8576 KB Output is correct
13 Correct 13 ms 8576 KB Output is correct
14 Correct 12 ms 8576 KB Output is correct
15 Correct 10 ms 8448 KB Output is correct
16 Correct 10 ms 8576 KB Output is correct
17 Correct 10 ms 8448 KB Output is correct
18 Correct 10 ms 8448 KB Output is correct
19 Correct 10 ms 8448 KB Output is correct
20 Correct 10 ms 8448 KB Output is correct
21 Correct 10 ms 8448 KB Output is correct
22 Correct 13 ms 8576 KB Output is correct
23 Correct 10 ms 8448 KB Output is correct
24 Correct 10 ms 8576 KB Output is correct
25 Correct 10 ms 8448 KB Output is correct
26 Correct 10 ms 8448 KB Output is correct
27 Correct 10 ms 8448 KB Output is correct
28 Correct 10 ms 8448 KB Output is correct
29 Correct 10 ms 8448 KB Output is correct
30 Correct 10 ms 8448 KB Output is correct
31 Correct 10 ms 8448 KB Output is correct
32 Correct 11 ms 8448 KB Output is correct
33 Correct 13 ms 8576 KB Output is correct

Subtask #2
0 / 89.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 8192 KB Output is correct
2 Correct 8 ms 8192 KB Output is correct
3 Correct 8 ms 8192 KB Output is correct
4 Correct 9 ms 8192 KB Output is correct
5 Correct 10 ms 8320 KB Output is correct
6 Correct 10 ms 8448 KB Output is correct
7 Correct 10 ms 8448 KB Output is correct
8 Correct 10 ms 8448 KB Output is correct
9 Correct 10 ms 8448 KB Output is correct
10 Correct 10 ms 8448 KB Output is correct
11 Correct 10 ms 8576 KB Output is correct
12 Correct 10 ms 8576 KB Output is correct
13 Correct 13 ms 8576 KB Output is correct
14 Correct 12 ms 8576 KB Output is correct
15 Correct 10 ms 8448 KB Output is correct
16 Correct 10 ms 8576 KB Output is correct
17 Correct 10 ms 8448 KB Output is correct
18 Correct 10 ms 8448 KB Output is correct
19 Correct 10 ms 8448 KB Output is correct
20 Correct 10 ms 8448 KB Output is correct
21 Correct 10 ms 8448 KB Output is correct
22 Correct 13 ms 8576 KB Output is correct
23 Correct 10 ms 8448 KB Output is correct
24 Correct 10 ms 8576 KB Output is correct
25 Correct 10 ms 8448 KB Output is correct
26 Correct 10 ms 8448 KB Output is correct
27 Correct 10 ms 8448 KB Output is correct
28 Correct 10 ms 8448 KB Output is correct
29 Correct 10 ms 8448 KB Output is correct
30 Correct 10 ms 8448 KB Output is correct
31 Correct 10 ms 8448 KB Output is correct
32 Correct 11 ms 8448 KB Output is correct
33 Correct 13 ms 8576 KB Output is correct
34 Execution timed out 96 ms 7416 KB Time limit exceeded (wall clock)
35 Halted 0 ms 0 KB -