AcWing 1113. 红与黑
原题链接
简单
作者:
我要出去乱说
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2021-01-30 23:23:30
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所有人可见
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阅读 406
#include <iostream>
#include <algorithm>
using namespace std;
const int N = 25;
char ch[N][N];
int n, m;
int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1};
int dfs(int x, int y)
{
int cnt = 1;
ch[x][y] = '#'; //走过就堵死,防止重复计算,类似记忆化搜索
for (int i = 0; i < 4; i ++ ) //经典N皇后走格子问题
{
int a = x + dx[i], b = y + dy[i];
if (a >= 0 && a < n && b >= 0 && b < m && ch[a][b] == '.') //下一步在范围内且能走,则递归
cnt += dfs(a, b);
}
return cnt;
}
int main()
{
while (cin >> m >> n, n || m) //注意是有多组输入的,以0 0 结束输入
{
int x, y; //x,y用于定位起点坐标
for (int i = 0; i < n; i ++ )
for (int j = 0; j < m; j ++ )
{
cin >> ch[i][j];
if (ch[i][j] == '@')
x = i, y = j;
}
cout << dfs(x, y) << endl;
}
return 0;
}
懂了