CF977D Divide by three, multiply by two

题目链接

我同学在旁边做者道题，我也看了一下

真的好水难

一看这道题，直接搜索

剪枝是不可能剪枝的一辈子不可能

Code

#include <cstdio>
#include <iostream>
#include <algorithm>
using namespace std;
const long long MAXN = 105;

long long n;
long long a[MAXN],b[MAXN];
bool sign = false;
bool flag[MAXN];

void dfs(long long now){
	if (now == n){
		for (int i = 1 ; i <= n ; i++){
			printf("%lld ",b[i]);
		}
		sign = true;
		return ;
	}

	if (sign == true) return ;

	for (int i = 1 ; i <= n ; i++){
		if (flag[i] == true) continue;
		if(flag[i] == false){
			if (b[now] * 2 == a[i] || (a[i] * 3 == b[now])){ //由于要当p[i] % 3 = 0 时
				b[now + 1] = a[i];
				flag[i] = true;
				dfs(now + 1);
				flag[i] = false;
			}
		}
	}	

	return ;
}

int main(){
	scanf("%lld",&n);

	for (int i = 1 ; i <= n ; i++) scanf("%lld",&a[i]);

	for (int i = 1 ; i <= n ; i++){
		flag[i] = true;
		b[1] = a[i];
		dfs(1);
		flag[i] = false;
	}

	return 0;
}