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  1. #include <bits/stdc++.h> 
  2.  
  3. using namespace std;  
  4.  
  5. typedef long long ll;  
  6. typedef pair<int, int> ii;  
  7.  
  8. const int INF = 1e9;  
  9. const ll LINF = 1e18;  
  10.  
  11. const int N = 2e2 + 5; 
  12.  
  13. int dx[4] = {-1, -1, 1, 1}; 
  14. int dy[4] = {-1, 1, -1, 1}; 
  15.  
  16. int n, m, sx, sy, tx, ty; 
  17. bool ban[N][N]; 
  18.  
  19. bool ok(int x, int y) {
  20. 	return (1 <= x && x <= n && 1 <= y && y <= n && !ban[x][y]);  
  21. }
  22.  
  23. int dist[N][N];  
  24.  
  25. void bfs(int sx, int sy) {
  26. 	for (int x = 1; x <= n; x++) {
  27. 		for (int y = 1; y <= n; y++) dist[x][y] = -1;  
  28. 	}
  29.  
  30. 	queue<ii> q;  
  31. 	dist[sx][sy] = 0;   
  32. 	q.push({sx, sy});  
  33.  
  34. 	while (!q.empty()) {
  35. 		ii u = q.front(); q.pop();  
  36. 		int x = u.first, y = u.second;  
  37.  
  38. 		for (int i = 0; i < 4; i++) {
  39. 			int nx = x, ny = y;  
  40. 			while (ok(nx + dx[i], ny + dy[i])) {
  41. 				nx += dx[i], ny += dy[i]; 
  42. 				if (dist[nx][ny] == -1) {
  43. 					dist[nx][ny] = dist[x][y] + 1;   
  44. 					q.push({nx, ny});  
  45. 				}
  46. 			}
  47. 		}
  48. 	}
  49. }
  50.  
  51. int main() {
  52. 	ios::sync_with_stdio(false); 
  53. 	cin.tie(nullptr); 	
  54. 	cin >> n >> m >> sx >> sy >> tx >> ty; 
  55.  
  56. 	for (int i = 0; i < m; i++) {
  57. 		int x, y; 
  58. 		cin >> x >> y; 
  59. 		ban[x][y] = true;  
  60. 	}
  61.  
  62. 	bfs(sx, sy);  
  63.  
  64. 	cout << dist[tx][ty] << '\n';
  65. }
Success #stdin #stdout 0.01s 5284KB
comments (?)
stdin 
8 3 7 2 1 4
5 4
3 4
4 7
stdout 
3
https://ideone.com/bdtIDf
language:
C++14 (gcc 8.3)
created:
296 days ago
visibility:
secret

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