Submission #948108

# Submission time Handle Problem Language Result Execution time Memory
948108 2024-03-17T15:20:19 Z packmani Mecho (IOI09_mecho) C++14
22 / 100
134 ms 7336 KB
#include<bits/stdc++.h>
using namespace std;
#define int long long int
int n,speed;
char inp[805][805];
int board[805][805];
bool visited[805][805];
queue<pair<int,int>> q;
pair<int,int> s,e;
int cr,cc,er,ec;
int dr[]={0,-1,0,1};
int dc[]={1,0,-1,0};
int maxTime=0;
int l,m,r;
int layer,tillNext,inNext;
bool bfs(int start)
{
	queue<pair<int,int>> tempq;
	memset(visited,0,sizeof(visited));
	int time=start;
	tempq.push({s.first,s.second});
	tillNext=1;
	inNext=0;
	layer=0;
	while(!tempq.empty())
	{
		cr = tempq.front().first;
		cc = tempq.front().second;
		tempq.pop();
		if(board[cr][cc]>time or inp[cr][cc]=='M')//bees have not reached this spot yet
		{
			//cout << time;
			for(int i=0;i<4;i++)
			{
				er = cr + dr[i];
				ec = cc + dc[i];
				if(er<0 or ec<0 or er>=n or ec>=n) continue;
				if(inp[er][ec]=='D') return 1;
				if(visited[er][ec]) continue;
				if(board[er][ec]==-1) continue;
				if(board[er][ec]<=time) continue;
				tempq.push({er,ec});
				visited[er][ec]=1;
				inNext++;
			}
		}
		tillNext--;
		if(tillNext==0)
		{
			tillNext = inNext;
			inNext = 0;
			layer++;
			if(layer%speed==0) time++;
		}
	}
	return 0;
}
int32_t main()
{
	cin.tie(0); ios_base::sync_with_stdio(false);
	cin >> n >> speed;
	for(int i=0;i<n;i++)
	{
		for(int j=0;j<n;j++)
		{
			cin >> inp[i][j];
			if(inp[i][j]=='T') board[i][j]=-1; //no one can traverse
			if(inp[i][j]=='H') 
			{
				board[i][j]=0; //not walkable since the 0th sec
				q.push({i,j});
			}
			if(inp[i][j]=='M') s={i,j};
			if(inp[i][j]=='D') e={i,j};
			if(inp[i][j]=='G') board[i][j] = 1000000;
		}
	}
	//bees
	while(!q.empty())
	{
		cr = q.front().first;
		cc = q.front().second;
		q.pop();
		for(int i=0;i<4;i++)
		{
			er = cr + dr[i];
			ec = cc + dc[i];
			if(er<0 or ec<0 or er>=n or ec>=n) continue;
			if(board[er][ec]==-1 or board[er][ec]=='D' or board[er][ec]=='M') continue;
			if(board[er][ec]<=board[cr][cc]+1) continue;
			board[er][ec]=board[cr][cc]+1;
			q.push({er,ec});
			maxTime=max(maxTime,board[er][ec]);
		}
	}
	l=0;
	r=maxTime;
	m = l + (r-l)/2;
	int best=-1;
	while(l<=r)
	{
		m = l + (r+0.5-l)/2;
		//cout << l << ' ' << r << ' ' << m << '\n';
		if(bfs(m)==1) 
		{
			l=m+1;
			best = max(best,m);
		}
		else r=m-1;
		

	}
	if(m==0 and bfs(0)==0) cout << -1;
	else cout << max(best,m);
}
# Verdict Execution time Memory Grader output
1 Correct 2 ms 4700 KB Output is correct
2 Incorrect 1 ms 4700 KB Output isn't correct
3 Correct 1 ms 4700 KB Output is correct
4 Correct 2 ms 4700 KB Output is correct
5 Incorrect 1 ms 4700 KB Output isn't correct
6 Incorrect 1 ms 4700 KB Output isn't correct
7 Incorrect 58 ms 6996 KB Output isn't correct
8 Correct 1 ms 4952 KB Output is correct
9 Incorrect 1 ms 4700 KB Output isn't correct
10 Incorrect 1 ms 4700 KB Output isn't correct
11 Incorrect 1 ms 4700 KB Output isn't correct
12 Correct 1 ms 4700 KB Output is correct
13 Incorrect 1 ms 4696 KB Output isn't correct
14 Correct 1 ms 4572 KB Output is correct
15 Correct 1 ms 4696 KB Output is correct
16 Incorrect 1 ms 4696 KB Output isn't correct
17 Incorrect 1 ms 4700 KB Output isn't correct
18 Correct 1 ms 4700 KB Output is correct
19 Incorrect 1 ms 4700 KB Output isn't correct
20 Correct 1 ms 4696 KB Output is correct
21 Incorrect 1 ms 4700 KB Output isn't correct
22 Correct 1 ms 4700 KB Output is correct
23 Incorrect 1 ms 4696 KB Output isn't correct
24 Correct 1 ms 4700 KB Output is correct
25 Incorrect 1 ms 4700 KB Output isn't correct
26 Incorrect 1 ms 4952 KB Output isn't correct
27 Correct 1 ms 4700 KB Output is correct
28 Correct 1 ms 4700 KB Output is correct
29 Incorrect 1 ms 4696 KB Output isn't correct
30 Correct 1 ms 4700 KB Output is correct
31 Incorrect 1 ms 4700 KB Output isn't correct
32 Incorrect 1 ms 4700 KB Output isn't correct
33 Correct 3 ms 6748 KB Output is correct
34 Incorrect 4 ms 6748 KB Output isn't correct
35 Correct 14 ms 6800 KB Output is correct
36 Incorrect 4 ms 6748 KB Output isn't correct
37 Correct 4 ms 6796 KB Output is correct
38 Correct 18 ms 6796 KB Output is correct
39 Incorrect 5 ms 6748 KB Output isn't correct
40 Incorrect 5 ms 6748 KB Output isn't correct
41 Incorrect 25 ms 6748 KB Output isn't correct
42 Incorrect 5 ms 6748 KB Output isn't correct
43 Correct 6 ms 6748 KB Output is correct
44 Incorrect 30 ms 6812 KB Output isn't correct
45 Incorrect 7 ms 6748 KB Output isn't correct
46 Incorrect 6 ms 6744 KB Output isn't correct
47 Correct 39 ms 6784 KB Output is correct
48 Incorrect 10 ms 6744 KB Output isn't correct
49 Correct 8 ms 6616 KB Output is correct
50 Incorrect 44 ms 6748 KB Output isn't correct
51 Correct 9 ms 6748 KB Output is correct
52 Incorrect 9 ms 6744 KB Output isn't correct
53 Incorrect 68 ms 6748 KB Output isn't correct
54 Correct 10 ms 6748 KB Output is correct
55 Incorrect 10 ms 6748 KB Output isn't correct
56 Correct 62 ms 6616 KB Output is correct
57 Incorrect 12 ms 6744 KB Output isn't correct
58 Incorrect 11 ms 6748 KB Output isn't correct
59 Correct 71 ms 6620 KB Output is correct
60 Incorrect 13 ms 6744 KB Output isn't correct
61 Incorrect 14 ms 6744 KB Output isn't correct
62 Correct 95 ms 6792 KB Output is correct
63 Correct 92 ms 6748 KB Output is correct
64 Incorrect 134 ms 6748 KB Output isn't correct
65 Incorrect 131 ms 6788 KB Output isn't correct
66 Correct 103 ms 6872 KB Output is correct
67 Correct 96 ms 6740 KB Output is correct
68 Correct 42 ms 6740 KB Output is correct
69 Incorrect 32 ms 6744 KB Output isn't correct
70 Incorrect 35 ms 6740 KB Output isn't correct
71 Incorrect 31 ms 6748 KB Output isn't correct
72 Incorrect 27 ms 6748 KB Output isn't correct
73 Incorrect 48 ms 7252 KB Output isn't correct
74 Incorrect 44 ms 7220 KB Output isn't correct
75 Incorrect 44 ms 7336 KB Output isn't correct
76 Correct 46 ms 7172 KB Output is correct
77 Correct 47 ms 7336 KB Output is correct
78 Correct 57 ms 7248 KB Output is correct
79 Incorrect 46 ms 7256 KB Output isn't correct
80 Incorrect 44 ms 7252 KB Output isn't correct
81 Correct 48 ms 7260 KB Output is correct
82 Incorrect 44 ms 7268 KB Output isn't correct
83 Incorrect 55 ms 7004 KB Output isn't correct
84 Correct 50 ms 7040 KB Output is correct
85 Incorrect 54 ms 7256 KB Output isn't correct
86 Incorrect 54 ms 7000 KB Output isn't correct
87 Correct 53 ms 7004 KB Output is correct
88 Incorrect 55 ms 7004 KB Output isn't correct
89 Incorrect 56 ms 7004 KB Output isn't correct
90 Correct 58 ms 6960 KB Output is correct
91 Incorrect 63 ms 7116 KB Output isn't correct
92 Correct 58 ms 7004 KB Output is correct