算法竞赛入门经典第二版 4 - 2

因为没有题目，所以我只是按照书上描述的写的，输入输出可能有点差错

#include 
#include 
using namespace std;
int Lu[10][10], n, sum = 0;
//检验正方形边长1~n - 1各种可能情况下是否能构成正方形
void dfs(int x, int y){
	int len = 1, flag;
	if (Lu[x + 1][y] != 1 || Lu[x][y + 1] != 1)
		return ;
	for ( len; len < n - x && len < n - y; len++){
		flag = 0;
		for (int i = 1; i <= len; i++)
			if (Lu[x][i] == 1)
				flag++;
		for (int i = 1; i <= len; i++)
			if (Lu[i][y] == 1)
				flag++;
		for (int i = 1; i <= len; i++)
			if (Lu[x + len][i] == 1)
				flag++;
		for (int i = 1; i <= len; i++)
			if (Lu[i][y + len] == 1)
				flag++;
		if (flag == 4 * len)
			sum++;
	}
	return ;
}
int main(){
	char a = '1';
	int x = 1, y;
	while (scanf("%d", &n) != EOF){
		memset(Lu, 0, sizeof(Lu));
		while(x != 0){
			scanf("%c%d%d", &a, &x, &y);
			if (a == 'V')
				Lu[x + 1][y] = 1;
			else if (a == 'H')
				Lu[x][y + 1] = 1;
		}
		for (int i = 1; i <= n; i++)
			for (int j = 1; j <= n; j++)
				dfs(i, j);
		printf("%d\n", sum);
	}
	return 0;
}