oj.uz

답안 #763915

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
763915 2023-06-23T03:12:49 Z hanlulu Mecho (IOI09_mecho) C++14
54 / 100
 176 ms 6124 KB 
//https://cses.fi/problemset/task/1707
#include <bits/stdc++.h>
using namespace std; 
/*
有点像793的题目，两次最短。Bee走出到每一个位置的最短，
然后二分答案，然后Mecho走最短的时侯每一个相邻是否可以走需要计算是否Bee先到。
如何处理一分钟走s步这里？dis记录当前的步数，每次走到相邻+1，但是时间可以用dis/s得到。
注意：一个位置如果bee先到，比如2s到，m 3s到，那么m就不能走，如果相等可以走，因为每一次都是m先走。
但是，终点要特殊处理。 能到达终点的周围四个点就可以到达。 
*/
int n,s;
char a[801][801];
int rdir[4] = {0,0,1,-1};
int cdir[4] = {1,-1,0,0};
vector<vector<int>> beetime(801,vector<int>(801,1e9));

int sx,sy,ex,ey;//起点和终点 

bool isok(int eat)//eat is how many time he stay at start point. 
{
	if (eat >= beetime[sx][sy]) return false;
	vector<vector<int>> mstep(801,vector<int>(801,1e9));
	//cout << eat << endl;
	queue<pair<int,int>> myq;
	mstep[sx][sy] = 0;
	myq.push({sx,sy}); 
	while (!myq.empty()) {
		int x = myq.front().first;
		int y = myq.front().second;
		myq.pop();
		for (int i = 0; i < 4; i++)
		{
			int newx = x + rdir[i];
			int newy = y + cdir[i];
			if (a[newx][newy] == 'D') return true;//终点不需要判断了。因为bee到不了。 
			if (newx <0 || newx == n || newy < 0 || newy == n) continue;
			if (a[newx][newy] == 'T' || a[newx][newy] == 'H' ) continue;
			if (mstep[newx][newy] <= mstep[x][y] + 1) continue;
			if (beetime[newx][newy] < ceil(1.0*(mstep[x][y]+1) /s) + eat) continue; 
			//if (beetime[newx][newy] <= (mstep[x][y]+1) /s + eat) continue; 
			//cout << newx << " " << newy << " " << (mstep[x][y]+1) /s + eat << endl;
			mstep[newx][newy] = mstep[x][y] + 1;
			
			myq.push({newx,newy});
		}		
	}
	//cout <<  mstep[2][2]  << endl;
	return false;
}
int main()
{
  	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	//freopen("nocross.in","r",stdin);
	//freopen("nocross.out","w",stdout);
 	cin >> n >> s;
	
	queue<pair<int,int>> myq;
 	for (int i = 0; i < n; i++) 
 	for (int j = 0; j < n; j++) 
 	{
 		cin >> a[i][j];
 		if (a[i][j] == 'M') sx = i, sy = j;
 		if (a[i][j] == 'D') ex = i, ey = j;
 		if (a[i][j] == 'H') {
 			beetime[i][j] = 0;
 			myq.push({i,j});
		};
	}	

  	//find beetime
	while (!myq.empty()) {
		int x = myq.front().first;
		int y = myq.front().second;
		myq.pop();
		for (int i = 0; i < 4; i++)
		{
			int newx = x + rdir[i];
			int newy = y + cdir[i];
			if (newx <0 || newx == n || newy < 0 || newy == n) continue;
			if (a[newx][newy] == 'T' ||  a[newx][newy] == 'H' ||  a[newx][newy] == 'D') continue;
			if (beetime[newx][newy] <= beetime[x][y] + 1) continue;
			
			beetime[newx][newy] = beetime[x][y] + 1;			
			myq.push({newx,newy});
		}
	}
	  //	cout << beetime[2][2]<< endl;
  	//bin the answer
  	int ans = -1;
  	int l = 0, r =  n*n, mid;
  	while (l <= r) {
  		mid = (l+r)/2;
  		//cout << "mid " << mid <<  endl;
		if (isok(mid)) {
			ans = mid;
			l = mid + 1;
		}	
		else r = mid - 1;
	}
	cout << ans << '\n'; 
	return 0;
}

Subtask #1
54.0 / 100.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 4 ms 5372 KB Output isn't correct
2 Incorrect 4 ms 5372 KB Output isn't correct
3 Incorrect 3 ms 5352 KB Output isn't correct
4 Incorrect 4 ms 5372 KB Output isn't correct
5 Correct 3 ms 5352 KB Output is correct
6 Correct 4 ms 5392 KB Output is correct
7 Correct 101 ms 6056 KB Output is correct
8 Incorrect 4 ms 5392 KB Output isn't correct
9 Correct 4 ms 5372 KB Output is correct
10 Correct 4 ms 5392 KB Output is correct
11 Correct 3 ms 5352 KB Output is correct
12 Correct 4 ms 5392 KB Output is correct
13 Correct 3 ms 5332 KB Output is correct
14 Correct 5 ms 5460 KB Output is correct
15 Incorrect 6 ms 5416 KB Output isn't correct
16 Correct 4 ms 5392 KB Output is correct
17 Incorrect 6 ms 5440 KB Output isn't correct
18 Correct 5 ms 5432 KB Output is correct
19 Incorrect 7 ms 5452 KB Output isn't correct
20 Correct 5 ms 5392 KB Output is correct
21 Incorrect 7 ms 5472 KB Output isn't correct
22 Correct 8 ms 5452 KB Output is correct
23 Incorrect 6 ms 5452 KB Output isn't correct
24 Correct 5 ms 5432 KB Output is correct
25 Incorrect 7 ms 5472 KB Output isn't correct
26 Correct 7 ms 5492 KB Output is correct
27 Incorrect 7 ms 5472 KB Output isn't correct
28 Correct 8 ms 5492 KB Output is correct
29 Incorrect 7 ms 5492 KB Output isn't correct
30 Correct 7 ms 5480 KB Output is correct
31 Incorrect 7 ms 5492 KB Output isn't correct
32 Correct 8 ms 5512 KB Output is correct
33 Incorrect 10 ms 5704 KB Output isn't correct
34 Correct 11 ms 5696 KB Output is correct
35 Correct 30 ms 5684 KB Output is correct
36 Incorrect 12 ms 5756 KB Output isn't correct
37 Correct 13 ms 5748 KB Output is correct
38 Correct 37 ms 5720 KB Output is correct
39 Incorrect 12 ms 5776 KB Output isn't correct
40 Correct 13 ms 5776 KB Output is correct
41 Correct 48 ms 5744 KB Output is correct
42 Incorrect 14 ms 5828 KB Output isn't correct
43 Correct 15 ms 5840 KB Output is correct
44 Correct 59 ms 5804 KB Output is correct
45 Incorrect 16 ms 5916 KB Output isn't correct
46 Correct 17 ms 5864 KB Output is correct
47 Correct 66 ms 5852 KB Output is correct
48 Incorrect 16 ms 5904 KB Output isn't correct
49 Correct 15 ms 5972 KB Output is correct
50 Correct 78 ms 5884 KB Output is correct
51 Incorrect 17 ms 5956 KB Output isn't correct
52 Correct 20 ms 5956 KB Output is correct
53 Correct 97 ms 5936 KB Output is correct
54 Incorrect 20 ms 6008 KB Output isn't correct
55 Correct 18 ms 5972 KB Output is correct
56 Correct 114 ms 6080 KB Output is correct
57 Incorrect 20 ms 6024 KB Output isn't correct
58 Correct 21 ms 6032 KB Output is correct
59 Correct 131 ms 5992 KB Output is correct
60 Incorrect 21 ms 6072 KB Output isn't correct
61 Correct 20 ms 6052 KB Output is correct
62 Correct 141 ms 6024 KB Output is correct
63 Correct 111 ms 6020 KB Output is correct
64 Correct 176 ms 6032 KB Output is correct
65 Correct 135 ms 6036 KB Output is correct
66 Incorrect 121 ms 6036 KB Output isn't correct
67 Correct 106 ms 6032 KB Output is correct
68 Correct 54 ms 6056 KB Output is correct
69 Correct 44 ms 6060 KB Output is correct
70 Correct 34 ms 6056 KB Output is correct
71 Correct 40 ms 6056 KB Output is correct
72 Correct 27 ms 6044 KB Output is correct
73 Correct 38 ms 5948 KB Output is correct
74 Correct 67 ms 5996 KB Output is correct
75 Correct 82 ms 6000 KB Output is correct
76 Correct 71 ms 6044 KB Output is correct
77 Correct 70 ms 6052 KB Output is correct
78 Correct 88 ms 6036 KB Output is correct
79 Correct 53 ms 6064 KB Output is correct
80 Correct 68 ms 6068 KB Output is correct
81 Correct 80 ms 6072 KB Output is correct
82 Correct 68 ms 6068 KB Output is correct
83 Correct 95 ms 6028 KB Output is correct
84 Correct 80 ms 6024 KB Output is correct
85 Correct 89 ms 6056 KB Output is correct
86 Correct 91 ms 6076 KB Output is correct
87 Correct 88 ms 6020 KB Output is correct
88 Correct 96 ms 6124 KB Output is correct
89 Correct 101 ms 6040 KB Output is correct
90 Correct 97 ms 6056 KB Output is correct
91 Correct 95 ms 6068 KB Output is correct
92 Correct 106 ms 6052 KB Output is correct