公式求斜标记法

#include <cstdio>
#include <iostream>
using namespace std;

bool col[15], recline1[30], recline2[30];//列，左斜，右斜标记(想想为什么要把斜的设为两倍大?)
int queen[15], n;//记录每一行的横坐标

void backtracking(int idx) {
	if (idx == n + 1) {
		for (int k = 1; k <= n; k++) {
			printf("    %d", queen[k]);
		}
		printf("\n");
		return ;
	}
	for (int j = 1; j <= n; j++) {
		queen[idx] = j;
		if (!col[queen[idx]] && !recline1[n - queen[idx] + idx] && !recline2[queen[idx] + idx - 1]) {//毫无问题的完美公式(生物课上闲着无聊推的)
			col[queen[idx]] = 1;
			recline1[n - queen[idx] + idx] = 1;
			recline2[queen[idx] + idx - 1] = 1;
			backtracking(idx);
			col[queen[idx]] = 0;
			recline1[n - queen[idx] + idx] = 0;
			recline2[queen[idx] + idx - 1] = 0;
		}
	}
}

int main() {
	cin >> n;
	if (n <= 3) {
		cout << "no solute!";
		return 0;
	}//直接特判
	backtracking(1);
	return 0;
}