답안 #132330

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
132330	2019-07-18T17:33:54 Z	bogdan10bos	007 (CEOI14_007)	C++14	100 / 100	365 ms	17784 KB

007

/// 00:04 why?
#include <bits/stdc++.h>

using namespace std;

const int NMAX = 2e5 + 5;

int N, M, S, D, A, B;
vector<int> edg[NMAX];

vector<int> BFS(int start)
{
	vector<int> d(N + 1, 1 << 30);
	d[start] = 0;
	queue<int> q;
	q.push(start);
	while(!q.empty())
	{
		int nod = q.front();
		q.pop();
		for(auto nxt: edg[nod])
			if(d[nxt] > d[nod] + 1)
			{
				d[nxt] = d[nod] + 1;
				q.push(nxt);
			}
	}
	return d;
}

int main()
{
	//freopen("1.in", "r", stdin);
	scanf("%d%d", &N, &M);
	scanf("%d%d%d%d", &S, &D, &A, &B);
	for(int i = 1; i <= M; i++)
	{
		int x, y;
		scanf("%d%d", &x, &y);
		edg[x].push_back(y);
		edg[y].push_back(x);
	}

	auto dS = BFS(S);
	auto dD = BFS(D);

	if(dD[A] + 1 <= dS[A] || dD[B] + 1 <= dS[B])
	{
		printf("-1\n");
		exit(0);
	}

	int timp = -1;
	if(dD[A] - dS[A] != dD[B] - dS[B])
		timp = min(dD[A] - dS[A], dD[B] - dS[B]);
	else
	{
		auto dA = BFS(A);
		auto dB = BFS(B);

		int maxStepsS = 0;
		for(int i = 1; i <= N; i++)
			if(dA[i] == dB[i] && dA[i] + dS[i] == dS[A])
				maxStepsS = max(maxStepsS, dS[i]);

		int maxStepsD = 0;
				for(int i = 1; i <= N; i++)
					if(dA[i] == dB[i] && dA[i] + dD[i] == dD[A])
						maxStepsD = max(maxStepsD, dD[i]);
		timp = min(dD[A] - dS[A], dD[B] - dS[B]);
		maxStepsD -= (dD[A] - dS[A]);
		if(maxStepsS < maxStepsD)	timp--;
	}
	printf("%d\n", timp);
	return 0;
}

Compilation message

007.cpp: In function 'int main()':
007.cpp:34:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &N, &M);
  ~~~~~^~~~~~~~~~~~~~~~
007.cpp:35:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d%d", &S, &D, &A, &B);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
007.cpp:39:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &x, &y);
   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1

30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	4984 KB	Output is correct
2	Correct	6 ms	4984 KB	Output is correct
3	Correct	6 ms	4984 KB	Output is correct
4	Correct	6 ms	4984 KB	Output is correct
5	Correct	6 ms	4984 KB	Output is correct
6	Correct	6 ms	4984 KB	Output is correct
7	Correct	6 ms	4984 KB	Output is correct
8	Correct	6 ms	4984 KB	Output is correct
9	Correct	6 ms	4984 KB	Output is correct
10	Correct	6 ms	4984 KB	Output is correct
11	Correct	6 ms	4984 KB	Output is correct
12	Correct	6 ms	4984 KB	Output is correct
13	Correct	6 ms	5112 KB	Output is correct
14	Correct	6 ms	4984 KB	Output is correct
15	Correct	6 ms	4984 KB	Output is correct
16	Correct	6 ms	5112 KB	Output is correct
17	Correct	6 ms	5112 KB	Output is correct
18	Correct	6 ms	5112 KB	Output is correct
19	Correct	6 ms	5112 KB	Output is correct
20	Correct	6 ms	4984 KB	Output is correct
21	Correct	6 ms	5112 KB	Output is correct
22	Correct	7 ms	4984 KB	Output is correct
23	Correct	6 ms	4984 KB	Output is correct
24	Correct	6 ms	4988 KB	Output is correct

Subtask #2

70.0 / 70.0

#	결과	실행 시간	메모리	Grader output
1	Correct	37 ms	6904 KB	Output is correct
2	Correct	53 ms	7780 KB	Output is correct
3	Correct	38 ms	7036 KB	Output is correct
4	Correct	50 ms	7932 KB	Output is correct
5	Correct	31 ms	6520 KB	Output is correct
6	Correct	33 ms	6776 KB	Output is correct
7	Correct	42 ms	7288 KB	Output is correct
8	Correct	43 ms	7416 KB	Output is correct
9	Correct	58 ms	7772 KB	Output is correct
10	Correct	192 ms	12340 KB	Output is correct
11	Correct	78 ms	9336 KB	Output is correct
12	Correct	105 ms	10488 KB	Output is correct
13	Correct	87 ms	9596 KB	Output is correct
14	Correct	59 ms	8312 KB	Output is correct
15	Correct	112 ms	10472 KB	Output is correct
16	Correct	96 ms	9848 KB	Output is correct
17	Correct	105 ms	10104 KB	Output is correct
18	Correct	123 ms	10232 KB	Output is correct
19	Correct	145 ms	11512 KB	Output is correct
20	Correct	256 ms	14200 KB	Output is correct
21	Correct	165 ms	12644 KB	Output is correct
22	Correct	175 ms	11640 KB	Output is correct
23	Correct	180 ms	12408 KB	Output is correct
24	Correct	185 ms	12536 KB	Output is correct
25	Correct	215 ms	12108 KB	Output is correct
26	Correct	143 ms	11656 KB	Output is correct
27	Correct	188 ms	12540 KB	Output is correct
28	Correct	201 ms	12536 KB	Output is correct
29	Correct	193 ms	13108 KB	Output is correct
30	Correct	267 ms	14968 KB	Output is correct
31	Correct	183 ms	13688 KB	Output is correct
32	Correct	183 ms	12536 KB	Output is correct
33	Correct	188 ms	12792 KB	Output is correct
34	Correct	202 ms	13052 KB	Output is correct
35	Correct	177 ms	12792 KB	Output is correct
36	Correct	167 ms	13176 KB	Output is correct
37	Correct	165 ms	12652 KB	Output is correct
38	Correct	225 ms	14072 KB	Output is correct
39	Correct	236 ms	13944 KB	Output is correct
40	Correct	249 ms	15480 KB	Output is correct
41	Correct	365 ms	17784 KB	Output is correct