luogu 3812 【模板】 线性基
线性基是一个支持在集合里插入数并查询最大子集异或值
1 #include<iostream> 2 #include<cstdio> 3 #include<cstring> 4 #include<cstdlib> 5 #include<cmath> 6 #include<algorithm> 7 #include<queue> 8 #include<vector> 9 #include<map> 10 #include<set> 11 #define ll long long 12 #define db double 13 #define inf 2139062143 14 #define MAXN 100100 15 #define MOD 998244353 16 #define rep(i,s,t) for(register int i=(s),i##__end=(t);i<=i##__end;++i) 17 #define dwn(i,s,t) for(register int i=(s),i##__end=(t);i>=i##__end;--i) 18 #define ren for(register int i=fst[x];i;i=nxt[i]) 19 #define pb(i,x) vec[i].push_back(x) 20 #define pls(a,b) (a+b)%MOD 21 #define mns(a,b) (a-b+MOD)%MOD 22 #define mul(a,b) (1LL*(a)*(b))%MOD 23 using namespace std; 24 inline ll read() 25 { 26 ll x=0,f=1;char ch=getchar(); 27 while(!isdigit(ch)) {if(ch=='-') f=-1;ch=getchar();} 28 while(isdigit(ch)) {x=x*10+ch-'0';ch=getchar();} 29 return x*f; 30 } 31 ll p[70];int n,m; 32 void ins(ll x) {dwn(i,63,0) if(x>>i&1LL) {if(!p[i]) {p[i]=x;break;}x^=p[i];}} 33 ll query(ll res=0) {dwn(i,63,0) res=max(res,res^p[i]);return res;} 34 int main() 35 { 36 n=read();rep(i,1,n) ins(read());printf("%lld\n",query()); 37 }
