DFS——分成互质组

​​​​​​​分成互质组

        按题意模拟暴搜即可，实现如下。

#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for(int i = a;i<n;i++)
#define per(i,a,n) for(int i = n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
#define yes cout<<"YES"<<'\n';
#define no cout<<"NO"<<'\n';
#define endl '\n';
#define R register
typedef vector<int> VI;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll MOD=1000000007;
int rnd(int x) {return mrand() % x;}
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;};
ll lcm(int a,int b){return a*b/gcd(a,b);};

int n;
int a[12];
int ans=20;
vector<VI> v;

void dfs(int x){
	if(x==n){
		ans=min(ans,SZ(v));
		return;
	}
	rep(i,0,SZ(v)+1){
		if(i==SZ(v)){
			v.pb({a[x]});
			dfs(x+1);
			v.pop_back();
		}else{
			bool ok=1;
			for(auto c:v[i]){
				if(gcd(a[x],c)!=1){
					ok=0;
					break;
				}
			}
			if(ok){
				v[i].pb(a[x]);
				dfs(x+1);
				v[i].pop_back();
			}
		}
	}
}

int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin>>n;
	rep(i,0,n) cin>>a[i];
	dfs(0);
	cout<<ans<<endl;
	return 0;
}