# Untitled

unknown
plain_text
16 days ago
2.2 kB
2
Indexable
Never
```#include <iostream>
using namespace std;

struct Point {
int x, y;
Point(int _x, int _y) : x(_x), y(_y) {}
};

struct Queue {
Point elements[1000000];
int front, rear;

Queue() : front(0), rear(-1) {}

void push(Point p) {
elements[++rear] = p;
}

Point pop() {
return elements[front++];
}

bool isEmpty() {
return front > rear;
}
};

int T, n, m, p, q, s, t;
int board[201][201];
bool visited[201][201];

int dx[4] = {1, -1, -1, 1};
int dy[4] = {1, 1, -1, -1};

bool isValid(int x, int y) {
return x >= 1 && x <= n && y >= 1 && y <= n;
}

bool canMove(int x, int y) {
for (int i = 1; i <= m; i++) {
int r = ri[i], c = ci[i];
if ((x - p) * (c - q) == (y - q) * (r - p) && (x - p) * (x - r) + (y - q) * (y - c) < (x - r) * (x - r) + (y - c) * (y - c))
return false;
}
return true;
}

void push(Point p, Queue &q) {
q.push(p);
}

Point pop(Queue &q) {
return q.pop();
}

bool isEmpty(Queue &q) {
return q.isEmpty();
}

int bfs() {
Queue q;
push(Point(p, q), q);
visited[p][q] = true;
int level = 0;

while (!isEmpty(q)) {
int size = q.rear - q.front + 1;
while (size--) {
Point point = pop(q);
int x = point.x, y = point.y;

if (x == s && y == t)
return level;

for (int i = 0; i < 4; i++) {
int nx = x + dx[i], ny = y + dy[i];
if (isValid(nx, ny) && !visited[nx][ny] && canMove(nx, ny)) {
visited[nx][ny] = true;
push(Point(nx, ny), q);
}
}
}
level++;
}
return -1;
}

int main() {
cin >> T;
while (T--) {
cin >> n >> m >> p >> q >> s >> t;
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= n; j++) {
board[i][j] = 0;
visited[i][j] = false;
}
}

for (int i = 1; i <= m; i++) {
int r, c;
cin >> r >> c;
board[r][c] = 1;
}

cout << bfs() << endl;
}

return 0;
}
```