CF1416C XOR Inverse（字典树+贪心）

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#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll, ll>PLL;
typedef pair<int, int>PII;
typedef pair<double, double>PDD;
#define I_int ll
inline ll read()
{
    ll x = 0, f = 1;
    char ch = getchar();
    while(ch < '0' || ch > '9')
    {
        if(ch == '-')f = -1;
        ch = getchar();
    }
    while(ch >= '0' && ch <= '9')
    {
        x = x * 10 + ch - '0';
        ch = getchar();
    }
    return x * f;
}
#define read read()
#define closeSync ios::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define multiCase int T;cin>>T;for(int t=1;t<=T;t++)
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define repp(i,a,b) for(int i=(a);i<(b);i++)
#define per(i,a,b) for(int i=(a);i>=(b);i--)
#define perr(i,a,b) for(int i=(a);i>(b);i--)
ll ksm(ll a, ll b, ll p)
{
    ll res = 1;
    while(b)
    {
        if(b & 1)res = res * a % p;
        a = a * a % p;
        b >>= 1;
    }
    return res;
}

const int inf = 0x3f3f3f3f;
#define PI acos(-1)
const int maxn=3e5+100;
const double eps=1e-7;
const ll mod=987654321;

ll n;
int tr[maxn*40][2],idx;
ll dep[40][2];
vector<int>node[maxn*40];

int gnew(){
	idx++;
	tr[idx][0]=tr[idx][1]=0;
	node[idx].clear();
	return idx;
}

void insert(ll x,int cur){
	int p=0;
	for(int i=30;i>=0;i--){
		int now=(x>>i)&1;
		if(!tr[p][now]) tr[p][now]=gnew();
		p=tr[p][now];
		node[p].push_back(cur);
		
	}
}

void dfs(int pos,int d){
	if(d==-1) return ;
	int l=tr[pos][0],r=tr[pos][1];
	ll res=0;
	int sizl=node[l].size(),sizr=node[r].size();
	for(int i=0,j=0;i<sizl;i++){
		while(j<sizr&&node[l][i]>node[r][j]) j++;
		res+=j;
	}
	dep[d][0]+=res;
	dep[d][1]+=1ll*sizl*sizr-res;
	if(l) dfs(l,d-1);
	if(r) dfs(r,d-1);
}

int main(){
	idx=-1;
	gnew();
	n=read;
	rep(i,1,n){
		ll x=read;
		insert(x,i);
	}
	dfs(0,30);
	ll res=0,x=0;
	rep(i,0,30){
		if(dep[i][0]<=dep[i][1]){
			res+=dep[i][0];///this is 0
		}
		else{
			res+=dep[i][1];
			x=x|(1<<i);
		}
	}
	cout<<res<<" "<<x<<endl;
	
	
	
	
	
	
	return 0;
}