#include<iostream>
#include<cstring>
#include<string>
using namespace std;
int visited[9];
int K,N,counts,way;
char map[9][9];
void dfs(int k) {
if (way == K) {
counts++;
return;
}
if (k >= N) {
return;
}
for (int i = 0; i < N; i++) {
if (map[k][i] == '#'&&visited[i]==0) {
visited[i] = 1;
way++;
dfs(k + 1);
way--;
visited[i] = 0;
}
}
dfs(k + 1);
}
int main() {
while (cin >> N >> K) {
if (N == -1)
break;
memset(visited, 0, sizeof(visited));
memset(map, 0, sizeof(map));
counts=way = 0;
for (int i = 0; i < N; i++) {
for (int j = 0; j < N; j++) {
cin >> map[i][j];
}
}
dfs(0);
cout << counts << endl;
}
}
POJ-棋盘问题(DFS)
最新推荐文章于 2021-06-03 20:24:22 发布