oj.uz

Submission #103681

# Submission time Handle Problem Language Result Execution time Memory
103681 2019-04-02T04:16:23 Z tugushka Mecho (IOI09_mecho) C++14
57 / 100
 506 ms 66560 KB 
#include<bits/stdc++.h>
#define mp make_pair
#define pb push_back
using namespace std;

using pii = pair < short, short >;
const int N = 805;
const int dx[] = {1, -1, 0, 0}, dy[] = {0, 0, 1, -1};

char a[N][N];
pii mecho, home;
int n, s, hive[N][N];
bool used[N][N];

void hive_bfs(){
	memset( hive, 11, sizeof(hive) );
	queue < pii > q;
	for(int i = 0 ; i < n ; i++) for(int j = 0 ; j < n ; j++){
		if( a[i][j] == 'H' ){
			q.push( mp( i, j ) );
			hive[i][j] = 0;
		}
	}

	int dis = 0;
	while( !q.empty() ){
		dis += s;
		int sz = q.size();
		while( sz-- ){
			int x, y;
			tie(x, y) = q.front();
			q.pop();
			for(int i = 0 ; i < 4 ; i++){
				int tx = x+dx[i], ty = y+dy[i];
				if( tx < 0 || ty < 0 || tx >= n || ty >= n ) continue;
				if( a[tx][ty] == 'G' && hive[tx][ty] > 2e6 ){
					hive[tx][ty] = dis;
					q.push( mp( tx, ty ) );
				}
			}
		}
	}

	/*
	for(int i = 0 ; i < n ; i++){
		for(int j = 0 ; j < n ; j++){
			if( hive[i][j] > 2e6 ) printf("@@ ");
			else printf("%2d ", hive[i][j]);
		}
		printf("\n");
	}
	*/
}

bool mecho_bfs(int start_time){
	memset( used, 0, sizeof(used) );

	queue < pii > q;
	q.push( mecho );

	int dis = start_time;
	while( !q.empty() ){
		dis++;
		// cout << "dis " << dis << " : ";

		int sz = q.size();
		while( sz-- ){
			short x, y;
			tie(x, y) = q.front();
			q.pop();
			for(int i = 0 ; i < 4 ; i++){
				short tx = x+dx[i], ty = y+dy[i];
				if( tx < 0 || ty < 0 || tx >= n || ty >= n ) continue;
				if( !used[tx][ty] && a[tx][ty] == 'G' && hive[tx][ty] > dis ){
					used[tx][ty] = 1;
					if( used[ home.first ][ home.second ] ){
						return true;
					}
					// cout << "( " << tx << ',' << ty << " ), ";
					q.push( mp( tx, ty ) );
				}
			}
		}
		// cout << endl;
	}

	return used[ home.first ][ home.second ];
}

int main(){
	scanf("%d %d", &n, &s);
	for(int i = 0 ; i < n ; i++){
		scanf("%s", a[i]);
	}
	hive_bfs();
	for(int i = 0 ; i < n ; i++) for(int j = 0 ; j < n ; j++){
		if( a[i][j] == 'D' ){
			home = mp( i, j );
			a[i][j] = 'G';
		}
		if( a[i][j] == 'M' ){
			mecho = mp( i, j );
		}
	}

	if( !mecho_bfs( 0 ) ){
		printf("-1\n");
		return 0;
	}

	int l = 0, r = n*n, res;
	while( l <= r ){
		int mid = (l+r)/2;

		if( mecho_bfs( s*(mid) ) ){
			res = mid;
			l = mid+1;
		} else {
			r = mid-1;
		}
	}

	/*
	int res = 0;
	while( mecho_bfs( s*(res+1) ) ) res++;
	*/
	cout << res << endl;
}

Compilation message

mecho.cpp: In function 'int main()':
mecho.cpp:91:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d", &n, &s);
  ~~~~~^~~~~~~~~~~~~~~~~
mecho.cpp:93:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%s", a[i]);
   ~~~~~^~~~~~~~~~~~
mecho.cpp:127:10: warning: 'res' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout << res << endl;
          ^~~

Subtask #1
57.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 3456 KB Output is correct
2 Correct 5 ms 3456 KB Output is correct
3 Correct 5 ms 3584 KB Output is correct
4 Correct 5 ms 3456 KB Output is correct
5 Correct 5 ms 3456 KB Output is correct
6 Correct 5 ms 3584 KB Output is correct
7 Correct 116 ms 4316 KB Output is correct
8 Correct 5 ms 3456 KB Output is correct
9 Correct 5 ms 3584 KB Output is correct
10 Correct 5 ms 3456 KB Output is correct
11 Correct 5 ms 3548 KB Output is correct
12 Incorrect 5 ms 3584 KB Output isn't correct
13 Incorrect 5 ms 3456 KB Output isn't correct
14 Correct 5 ms 3584 KB Output is correct
15 Correct 6 ms 3584 KB Output is correct
16 Correct 5 ms 3456 KB Output is correct
17 Correct 5 ms 3584 KB Output is correct
18 Correct 5 ms 3584 KB Output is correct
19 Correct 5 ms 3584 KB Output is correct
20 Correct 4 ms 3584 KB Output is correct
21 Correct 5 ms 3584 KB Output is correct
22 Correct 5 ms 3500 KB Output is correct
23 Correct 6 ms 3584 KB Output is correct
24 Correct 6 ms 3456 KB Output is correct
25 Correct 5 ms 3584 KB Output is correct
26 Correct 5 ms 3584 KB Output is correct
27 Correct 5 ms 3584 KB Output is correct
28 Correct 5 ms 3584 KB Output is correct
29 Correct 5 ms 3584 KB Output is correct
30 Correct 5 ms 3584 KB Output is correct
31 Correct 5 ms 3584 KB Output is correct
32 Correct 6 ms 3584 KB Output is correct
33 Correct 6 ms 3712 KB Output is correct
34 Runtime error 493 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
35 Correct 25 ms 3712 KB Output is correct
36 Correct 8 ms 3840 KB Output is correct
37 Runtime error 506 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
38 Correct 30 ms 3840 KB Output is correct
39 Correct 12 ms 3840 KB Output is correct
40 Runtime error 499 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
41 Correct 37 ms 3840 KB Output is correct
42 Correct 10 ms 3968 KB Output is correct
43 Runtime error 468 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
44 Correct 56 ms 3840 KB Output is correct
45 Correct 11 ms 3968 KB Output is correct
46 Runtime error 480 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
47 Correct 76 ms 3968 KB Output is correct
48 Correct 10 ms 3968 KB Output is correct
49 Runtime error 451 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
50 Correct 66 ms 3968 KB Output is correct
51 Correct 12 ms 3968 KB Output is correct
52 Runtime error 499 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
53 Correct 100 ms 4088 KB Output is correct
54 Correct 14 ms 4096 KB Output is correct
55 Runtime error 488 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
56 Correct 109 ms 4088 KB Output is correct
57 Correct 15 ms 4096 KB Output is correct
58 Runtime error 472 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
59 Correct 137 ms 4216 KB Output is correct
60 Correct 16 ms 4088 KB Output is correct
61 Runtime error 494 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
62 Correct 135 ms 4096 KB Output is correct
63 Correct 125 ms 4216 KB Output is correct
64 Runtime error 395 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
65 Correct 179 ms 4088 KB Output is correct
66 Correct 149 ms 4088 KB Output is correct
67 Correct 32 ms 4044 KB Output is correct
68 Correct 53 ms 4336 KB Output is correct
69 Correct 51 ms 4088 KB Output is correct
70 Correct 42 ms 4088 KB Output is correct
71 Correct 44 ms 4088 KB Output is correct
72 Incorrect 34 ms 4088 KB Output isn't correct
73 Incorrect 83 ms 4204 KB Output isn't correct
74 Correct 71 ms 4184 KB Output is correct
75 Correct 76 ms 4292 KB Output is correct
76 Correct 66 ms 4232 KB Output is correct
77 Correct 65 ms 4212 KB Output is correct
78 Correct 47 ms 4216 KB Output is correct
79 Correct 60 ms 4344 KB Output is correct
80 Correct 67 ms 4224 KB Output is correct
81 Correct 72 ms 4216 KB Output is correct
82 Correct 65 ms 4216 KB Output is correct
83 Correct 90 ms 4216 KB Output is correct
84 Correct 81 ms 4224 KB Output is correct
85 Correct 92 ms 4216 KB Output is correct
86 Correct 88 ms 4216 KB Output is correct
87 Correct 88 ms 4188 KB Output is correct
88 Correct 96 ms 4192 KB Output is correct
89 Correct 96 ms 4324 KB Output is correct
90 Correct 104 ms 4224 KB Output is correct
91 Correct 101 ms 4240 KB Output is correct
92 Correct 98 ms 4216 KB Output is correct