[BZOJ3105] 线性基+博弈论

[BZOJ3105]

• 通过博弈论可以转化成求最大线性无关集合没学过博弈论看题的时候一脸懵逼

Code

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#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define per(i,a,b) for(int i=(a);i>=(b);i--)
#define ll long long
using namespace std;
const int lim=30;
const int N=200;
ll ans=0,sum=0;
int tmp[N],a[N],n;
void insert(int v){
	ll fuck=v;
	per(i,lim,0)if((v>>i)&1){
		if(a[i])v^=a[i];
		else{
			per(j,i-1,0)if((v>>j)&1)v^=a[j];
			rep(j,i+1,lim)if((a[j]>>i)&1)a[j]^=v;
			a[i]=v;
			ans-=fuck;
			break;
		}
	}
}
int main()
{
	scanf("%d",&n);
	rep(i,1,n)scanf("%d",&tmp[i]);
	rep(i,1,n)ans+=tmp[i],sum+=tmp[i];
	sort(tmp+1,tmp+n+1);
	per(i,n,1)insert(tmp[i]);
	if(ans==sum)ans=-1;
	printf("%lld",ans);
	return 0;
}

• 线性基模板