poj2766

简单题

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;

#define maxn 55

int vis[maxn][maxn];
bool map[maxn][maxn];
int n, r, sx, sy;
int dir[4][2] =
{
{ 1, 0 },
{ 0, -1 },
{ -1, 0 },
{ 0, 1 } };

void input()
{
    scanf("%d%d", &n, &r);
    memset(map, 0, sizeof(map));
    for (int i = 0; i < r; i++)
    {
        int a, b;
        scanf("%d%d", &a, &b);
        map[a][b] = true;
    }
    scanf("%d%d", &sx, &sy);
}

bool out(int x, int y)
{
    if (x == 0 || y == 0 || x == n + 1 || y == n + 1)
        return true;
    return false;
}

void work()
{
    int d;
    if (sx == 0)
        d = 0;
    if (sy == n + 1)
        d = 1;
    if (sx == n + 1)
        d = 2;
    if (sy == 0)
        d = 3;
    int x = sx;
    int y = sy;
    memset(vis, 0, sizeof(vis));
    while (1)
    {
        x += dir[d][0];
        y += dir[d][1];
        if (out(x, y))
        {
            printf("%d %d\n", x, y);
            return;
        }
        if (vis[x][y] & (1 << d))
            break;
        vis[x][y] += 1 << d;
        if (map[x][y])
            d = (d + 1) % 4;
    }
    printf("0 0\n");
}

int main()
{
    //freopen("t.txt", "r", stdin);
    int t;
    scanf("%d", &t);
    while (t--)
    {
        input();
        work();
    }
    return 0;
}