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#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; int n, k, c; char cc; bool p[10][10]; bool visx[10]; bool visy[10]; void dfs(int pos,int a) { if (a == k) { c++; return; } while (pos < n*n) { int x = pos / n; int y = pos % n; if (p[x][y] && !visx[x] && !visy[y]) { visx[x] = visy[y] = true; dfs(pos+1,a+1); visx[x] = visy[y] = false; } pos++; } return; } int main() { while (scanf(%d%d,&n,&k)!=EOF) { c = 0; if (n == -1 && k == -1) return 0; getchar(); memset(p,false,sizeof(p)); for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { cc = getchar(); if (cc == '#') p[i][j] = true; else p[i][j] = false; } getchar(); } memset(visx,false,sizeof(visx)); memset(visy, false, sizeof(visy)); dfs(0, 0); printf(%d ,c); } }