poj 3620 Avoid The Lakes

来源：互联网发布：圆形水池计算软件编辑：程序博客网时间：2024/05/18 22:45
很简单的dfs
/*Poj: 3620 Avoid The Lakes*/#include <iostream>#include <cstdio>#include <cstring>#include <string>#include <algorithm>#define MaxN 105using namespace std;int dirx[4] = {0, 0, -1, 1};int diry[4] = {-1, 1, 0, 0};bool map[MaxN][MaxN];bool visited[MaxN][MaxN];;int n, m, k;bool check(int x, int y){    if(x >= 1 && x <= n && y >= 1 && y <= m)        return true;    return false;}int dfs(int x, int y){    int total = 1;    for(int i = 0; i < 4; i++) {        int tmpx = x + dirx[i];        int tmpy = y + diry[i];        if(check(tmpx, tmpy) && !visited[tmpx][tmpy] && map[tmpx][tmpy]) {            visited[tmpx][tmpy] = true;            total += dfs(tmpx, tmpy);        }    }    return total;}int main(){       //freopen("data.in", "rb", stdin);    while(scanf("%d%d%d", &n, &m, &k) != EOF) {        memset(map, false, sizeof(map));        for(int i = 0; i < k; i++) {            int a, b;            scanf("%d%d", &a, &b);            map[a][b] = true;        }                memset(visited, false, sizeof(visited));            int res = 0;          for(int i = 1; i <= n; i++) {            for(int j = 1; j <= m; j++) {                if(!visited[i][j] && map[i][j]) {                    visited[i][j] = true;                    res = max(dfs(i, j), res);                }            }        }        printf("%d\n", res);            }        return 0;}