一些比较难懂的递归题目 c++

全排列问题

#include<cstdio>
const int maxn = 11;
int n, P[maxn], hashTable[maxn] = { false };

void generateP(int index) {
	if (index == n + 1) {
		for (int i = 1; i <= n; i++) {
			printf("%d", P[i]);
		}
		printf("\n");
		return;
	}
	for (int x = 1; x <= n; x++) {
		if (hashTable[x] == false) {
			P[index] = x;
			hashTable[x] = true;
			generateP(index + 1);
			hashTable[x] = false;
		}
	}
}

int main() {
	n = 3;
	generateP(1);
	return 0;
}

n皇后问题