답안 #103679

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
103679 2019-04-02T04:11:30 Z tugushka Mecho (IOI09_mecho) C++14
52 / 100
1000 ms 66560 KB
#include<bits/stdc++.h>
#define mp make_pair
#define pb push_back
using namespace std;

using pii = pair < int, int >;
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-- ){
			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( !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]);
   ~~~~~^~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 3584 KB Output is correct
2 Correct 5 ms 3456 KB Output is correct
3 Correct 5 ms 3456 KB Output is correct
4 Correct 5 ms 3456 KB Output is correct
5 Correct 5 ms 3584 KB Output is correct
6 Correct 4 ms 3584 KB Output is correct
7 Correct 218 ms 4272 KB Output is correct
8 Correct 6 ms 3584 KB Output is correct
9 Correct 5 ms 3456 KB Output is correct
10 Correct 4 ms 3456 KB Output is correct
11 Correct 5 ms 3456 KB Output is correct
12 Execution timed out 1082 ms 3584 KB Time limit exceeded
13 Incorrect 5 ms 3584 KB Output isn't correct
14 Correct 4 ms 3584 KB Output is correct
15 Correct 9 ms 3584 KB Output is correct
16 Correct 8 ms 3584 KB Output is correct
17 Correct 14 ms 3456 KB Output is correct
18 Correct 9 ms 3584 KB Output is correct
19 Correct 17 ms 3456 KB Output is correct
20 Correct 12 ms 3584 KB Output is correct
21 Correct 28 ms 3456 KB Output is correct
22 Correct 17 ms 3456 KB Output is correct
23 Correct 42 ms 3504 KB Output is correct
24 Correct 24 ms 3456 KB Output is correct
25 Correct 61 ms 3680 KB Output is correct
26 Correct 36 ms 3576 KB Output is correct
27 Correct 77 ms 3584 KB Output is correct
28 Correct 43 ms 3584 KB Output is correct
29 Correct 76 ms 3704 KB Output is correct
30 Correct 45 ms 3584 KB Output is correct
31 Correct 90 ms 3584 KB Output is correct
32 Correct 50 ms 3584 KB Output is correct
33 Execution timed out 1081 ms 3712 KB Time limit exceeded
34 Runtime error 325 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
35 Correct 15 ms 3840 KB Output is correct
36 Execution timed out 1081 ms 3840 KB Time limit exceeded
37 Runtime error 274 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
38 Correct 20 ms 3840 KB Output is correct
39 Execution timed out 1087 ms 3840 KB Time limit exceeded
40 Runtime error 315 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
41 Correct 21 ms 3840 KB Output is correct
42 Execution timed out 1082 ms 3968 KB Time limit exceeded
43 Runtime error 267 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
44 Correct 29 ms 3968 KB Output is correct
45 Execution timed out 1069 ms 3840 KB Time limit exceeded
46 Runtime error 262 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
47 Correct 30 ms 3968 KB Output is correct
48 Execution timed out 1069 ms 3968 KB Time limit exceeded
49 Runtime error 322 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
50 Correct 35 ms 3968 KB Output is correct
51 Execution timed out 1076 ms 3968 KB Time limit exceeded
52 Runtime error 293 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
53 Correct 51 ms 3968 KB Output is correct
54 Execution timed out 1082 ms 3968 KB Time limit exceeded
55 Runtime error 286 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
56 Correct 57 ms 4216 KB Output is correct
57 Execution timed out 1083 ms 4096 KB Time limit exceeded
58 Runtime error 303 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
59 Correct 75 ms 4088 KB Output is correct
60 Execution timed out 1087 ms 4088 KB Time limit exceeded
61 Runtime error 272 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
62 Correct 76 ms 4096 KB Output is correct
63 Correct 51 ms 4224 KB Output is correct
64 Runtime error 261 ms 66560 KB Execution killed with signal 9 (could be triggered by violating memory limits)
65 Execution timed out 1067 ms 4096 KB Time limit exceeded
66 Execution timed out 1085 ms 4088 KB Time limit exceeded
67 Correct 36 ms 4096 KB Output is correct
68 Correct 41 ms 4216 KB Output is correct
69 Correct 192 ms 4192 KB Output is correct
70 Correct 74 ms 4224 KB Output is correct
71 Correct 51 ms 4096 KB Output is correct
72 Execution timed out 1083 ms 4104 KB Time limit exceeded
73 Incorrect 537 ms 4348 KB Output isn't correct
74 Execution timed out 1082 ms 4324 KB Time limit exceeded
75 Correct 846 ms 4192 KB Output is correct
76 Correct 478 ms 4320 KB Output is correct
77 Execution timed out 1072 ms 4320 KB Time limit exceeded
78 Correct 39 ms 4220 KB Output is correct
79 Execution timed out 1061 ms 4224 KB Time limit exceeded
80 Correct 558 ms 4348 KB Output is correct
81 Correct 390 ms 4348 KB Output is correct
82 Correct 948 ms 4348 KB Output is correct
83 Correct 40 ms 4264 KB Output is correct
84 Correct 905 ms 4384 KB Output is correct
85 Correct 418 ms 4384 KB Output is correct
86 Correct 236 ms 4256 KB Output is correct
87 Correct 578 ms 4392 KB Output is correct
88 Correct 47 ms 4180 KB Output is correct
89 Correct 515 ms 4436 KB Output is correct
90 Correct 242 ms 4184 KB Output is correct
91 Correct 369 ms 4180 KB Output is correct
92 Correct 139 ms 4308 KB Output is correct