杭电2782

杭电2782

原题链接： http://acm.hdu.edu.cn/showproblem.php?pid=2782
思路：
先留个坑，这样的题夏令营应该不会有，回头再做
代码如下（未通过样例，也有错误，还需更改）

#include <algorithm>
#include <cstring>
#include <iostream>
#include "stdio.h"
using namespace std;

int a[625][625];
int visited[625][625];
int direction[4][2] = { 0, 1, -1, 0, 1, 0, 0, -1 };
int xs, ys;
int ans, d; //分别表示最大值，坐标位置，方向
int temp;
int m, n, r;
void dfs(int x, int y, int tm, int pre){
    for (int i = 0; i < 4; i++){
        int nx = x + direction[i][0];
        int ny = y + direction[i][1];
        if (nx >= 0 && nx < m && ny >= 0 && ny < n && a[nx][ny]!=1 && visited[nx][ny] != 1){
            visited[nx][ny] = 1; cout << "nx=" << nx << " ny=" << ny << endl;
            //temp++;

            dfs(nx, ny, ++tm, 0);
            if (tm > ans)  { d = i; xs = x; ys = y; ans = tm; }
            //temp--;
            visited[nx][ny] = 0;
        }
    }
}

int main(){
    int kase = 1;
    while (true){
        cin >> m >> n;
        if (m == 0 && n == 0) break;
        cin >> r;
        int tempx, tempy;
        memset(a, 0, sizeof(a));
        for (int i = 0; i < r; i++){
            cin >> tempx >> tempy;
            a[tempx][tempy] = 1;
        }
        ans = 0;
        d = 0;
        xs = 0, ys = 0;
        int flag = 1;

        for (int j = 0; j < n; j++){
            for (int i = 0; i < m; i++){
                if (a[i][j] != 1){
                    if (flag == 1) { ans = 1; xs = i; ys = j; flag = 0; }
                    memset(visited, 0, sizeof(visited));
                    temp = 1;
                    visited[i][j] = 1;
                    dfs(i, j, 1);
                }
            }
        }
        char dire;
        if (d == 0) dire = 'E';
        if (d == 1) dire = 'N';
        if (d == 2) dire = 'S';
        if (d == 3) dire = 'W';
        cout << "Case " << kase++ << ": " << ans << " " << xs << " " << ys << " " << dire << endl;
    }


    return 0;
}