View Code of Problem 1001

#include<stdio.h>
#include<queue>
#include<cstdlib>
#include<math.h>
#include<string.h>
#include<algorithm>
using namespace std;
int a[8][2] = { { -2, -1 }, { -2, 1 }, { -1, 2 }, { 1, 2 }, { 2, 1 }, { 2, -1 }, { 1, -2 }, { -1, -2 } };
int x, y, x1, Y, n;
int b[310][310];
struct node
{
	int x;
	int y;
	int f;
	int g;  
	bool operator <(const node &a) const
	{
		if (f == a.f) return g>a.g;
		return f > a.f;
	}
}str, str1;
priority_queue<node>Q;
int BFS()
{
	if (Q.top().x == x1&&Q.top().y == Y) return 0;
	while (!Q.empty())
	{
		str = Q.top(); Q.pop();
		for (int i = 0; i < 8; i++)
		{	
			str1 = str;
			str1.x += a[i][0]; str1.y += a[i][1];
			str1.g += 1; str1.f = abs(str1.x - x1) + abs(str1.y - Y)+ str1.g*3;
			if (str1.x == x1&&str1.y == Y) return str1.g;
			if (str1.x >= 0 && str1.x < n&&str1.y >= 0 && str1.y < n&&!b[str1.x][str1.y]){ b[str1.x][str1.y] = 1; Q.push(str1); }
		}
	}
}
int main()
{	
	int t;
	scanf("%d", &t);
	while (t--)
	{	
		int c = 0;
		scanf("%d", &n);
		memset(b, 0, sizeof(b));
		scanf("%d%d%d%d", &x, &y, &x1, &Y);
		while (!Q.empty())Q.pop();
		str.x = x; str.y = y; b[str.x][str.y]= 1;
		str.g = 0; str.f = abs(str.x - x1) + abs(str.y - Y) + str.g * 3;
		Q.push(str);
		c = BFS();
		printf("%d\n", c);
	}
	return 0;
}