就这个广搜爽

#include <iostream>
#include <cstdio>
#include <queue>
using namespace std;
struct node{
	int a[9] = {0}, ct = 0;
	bool vis[9] = {0};
};
bool check(node n){
	for(int i = 1; i < n.ct; i++){
		if(n.a[i] + i == n.a[n.ct] + n.ct || n.a[i] - i == n.a[n.ct] - n.ct) return 0;
	}return 1;
}int ct;
void bfs(){
	node n; 
	queue <node> q;
	q.push(n);
	while(!q.empty()){
		node head = q.front();
		q.pop();
		if(head.ct == 8){
			printf("sum=%d\n", ++ct);
			for(int i = 1; i <= 8; i++) printf("%2d", head.a[i]);
			cout << endl;
			continue;
		}for(int i = 1; i <= 8; i++){
			if(!head.vis[i]){
				node xx = head;
				xx.a[++xx.ct] = i;
				if(check(xx)){
					xx.vis[i] = 1;
					q.push(xx);
				}
			}
		}
	}
}
int main(){
	bfs();

	return 0;
}