简单题， BFS

#include 
      
        #include 
       
         #include 
        
          #include 
         
           using namespace std; #define maxn 105 struct Point {
    int x, y;     Point()     {
        }     Point(int xx, int yy): x(xx), y(yy)     {
        } }q[maxn * maxn]; int n; int map[maxn][maxn]; bool vis[maxn][maxn]; int dir[4][2] = {
    {
    1, 0},{
    0, 1},{-1, 0},{
    0, -1}}; void input() {
        memset(map, 0, sizeof(map)); for (int i = 1; i < n; i++) for (int j = 0; j < n; j++)         {
    int a, b;             scanf("%d%d", &a, &b);             a--;             b--;             map[a][b] = i;         } } int bfs(Point s) {
    int front, rear;     front = rear = 0;     q[rear++] = s;     vis[s.x][s.y] = true; int ret = 1; while (front != rear)     {
            Point p = q[front++]; for (int i = 0; i < 4; i++)         {
                Point a(p.x + dir[i][0], p.y + dir[i][1]); if (a.x >= 0 && a.y >= 0 && a.x < n && a.y < n && !vis[a.x][a.y] && map[a.x][a.y] == map[p.x][p.y])             {
                    vis[a.x][a.y] = true;                 q[rear++] = a;                 ret++;             }         }     } return ret; } bool work() {
        memset(vis, 0, sizeof(vis)); for (int i = 0; i < n; i++) for (int j = 0; j < n; j++) if (!vis[i][j])             {
    int x = bfs(Point(i, j)); if (x != n) return false;             } return true; } int main() {
    //freopen("t.txt", "r", stdin);     while (scanf("%d", &n), n)     {
            input(); if (work())             printf("good\n"); else             printf("wrong\n");     } return 0; }