算法设计与编程大赛 沙滩面积 题型：搜索

赛氪OJ-专注于算法竞赛的在线评测系统 (saikr.com)

#include <bits/stdc++.h>
using namespace std;
int n, m, k;
int g[110][110];
int vis[110][110];

int cnt;

void dfs(int x, int y, int step) {

	if (g[x][y] != '#')
		g[x][y] = '?';
	if (step == k)
		return;
	dfs(x + 1, y, step + 1);
	dfs(x, y + 1, step + 1);
	dfs(x - 1, y + 1, step + 1);
	dfs(x, y - 1, step + 1);
}

int main() {
	cin >> n >> m >> k;
	for (int i = 1 + 249; i <= n + 249; i++) {
		for (int j = 1 + 249; j <= m + 249; j++) {
			cin >> g[i][j];
		}
	}

	//找水域
	for (int i = 1 + 249; i <= n + 249; i++) {
		for (int j = 1 + 249; j <= m + 249; j++) {
			if (g[i][j] == '#') {
				dfs(i, j, 0);
			}
		}
	}



	for (int i = 1; i <= 500; i++) {
		for (int j = 1; j <= 500; j++) {
			if (g[i][j] == '?') {
				cnt++;
			}
		}
	}


	cout << cnt << endl;
	return 0;
}