题解 | 绝对值博弈

#include<bits/stdc++.h>
using namespace std;

int gcd(int a,int b){
	return b==0?a:gcd(b,a%b);
}

int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	
	int n;
	cin>>n;
	
	int ma_num=1,ma_gcd=1;
	
	vector<int> a(n+1,0);
	set<int> st;
	cin>>a[1];
	ma_num=a[1],ma_gcd=a[1];
	for(int i=2;i<=n;i++){
		cin>>a[i];
		ma_gcd=gcd(ma_gcd,a[i]);
		ma_num=max(a[i],ma_num);
	}
	
	int t=ma_num/ma_gcd;
	
	int res=t-n;
	
	if(res%2==0){
		cout<<"Bob"<<endl;
	}else{
		cout<<"Alice"<<endl;
	}
	
    return 0;
}