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three arrays
Trie+贪心。
#include <bits/stdc++.h>
using namespace std;
const int NPOS = -1;
struct Trie
{
struct Node
{
int cnt, ch[2];
};
vector<Node> v;
Trie() : v(1, Node{0, {NPOS, NPOS}}) {}
void add(int x)
{
for (int rt = 0, i = 29; ~i; --i)
{
int nxt = x >> i & 1;
if (v[rt].ch[nxt] == NPOS)
{
v[rt].ch[nxt] = v.size();
v.push_back(Node{0, {NPOS, NPOS}});
}
rt = v[rt].ch[nxt];
++v[rt].cnt;
}
}
};
int main()
{
int t, n;
for (scanf("%d", &t); t--;)
{
scanf("%d", &n);
Trie t[2];
for (int j = 0; j < 2; ++j)
for (int i = 0, x; i < n; ++i)
scanf("%d", &x), t[j].add(x);
vector<int> ans;
for (int i = 0, val; i < n; ++i)
{
for (int rt[2] = {val = 0, 0}, i = 29; ~i; --i)
{
#define OK(i, j) (t[i].v[rt[i]].ch[j] != NPOS && t[i].v[t[i].v[rt[i]].ch[j]].cnt)
if (OK(0, 1) && OK(1, 1))
rt[0] = t[0].v[rt[0]].ch[1], rt[1] = t[1].v[rt[1]].ch[1], val <<= 1;
else if (OK(0, 0) && OK(1, 0))
rt[0] = t[0].v[rt[0]].ch[0], rt[1] = t[1].v[rt[1]].ch[0], val <<= 1;
else if (OK(0, 1) && OK(1, 0))
rt[0] = t[0].v[rt[0]].ch[1], rt[1] = t[1].v[rt[1]].ch[0], val = val << 1 | 1;
else
rt[0] = t[0].v[rt[0]].ch[0], rt[1] = t[1].v[rt[1]].ch[1], val = val << 1 | 1;
--t[0].v[rt[0]].cnt, --t[1].v[rt[1]].cnt;
}
ans.push_back(val);
}
sort(ans.begin(), ans.end());
for (int i = 0; i < ans.size(); ++i)
printf("%d%c", ans[i], i + 1 < ans.size() ? ' ' : '\n');
}
}
permutation 1
#include<iostream>
#include<vector>
#include<algorithm>
#include<string.h>
using namespace std;
int n,k,l,t;
struct tem{
int a[30];
int size;
tem():size(0){}
};
tem p,q[1000000];
bool ed[100];
bool operator<(const tem& p,const tem& q){
if(n>=9)if(p.a[0]!=q.a[0])return p.a[0]<q.a[0];
for(int i=1;i<p.size;i++){
if(p.a[i]-p.a[i-1]==q.a[i]-q.a[i-1])continue;
return p.a[i]-p.a[i-1]<q.a[i]-q.a[i-1];
}
}
void dfs(tem p){
if(p.size>=min(n,8)){
q[++l]=p;
// cout<<l<<endl;
return;
}
for(int i=1;i<=n;i++){
if(!ed[i]){
p.a[p.size++]=i;
ed[i]=1;
dfs(p);
p.size--;
ed[i]=0;
}
}
}
int main(void){
cin>>t;
while(t--){
cin>>n>>k;
l=0;
memset(ed,0,sizeof(ed));
if(n>8){
ed[n]=1;
cout<<n<<" ";
for(int i=1;i<n-8;i++){
ed[i]=1;
cout<<i<<" ";
}}
dfs(p);
sort(q+1,q+l+1);
for(int i=0;i<q[k].size-1;i++){
cout<<q[k].a[i]<<" ";
}
cout<<q[k].a[q[k].size-1]<<endl;
}}
string matching
#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
const int maxn=1e6+10;
int T;
int ne[maxn];
char ch[maxn];
int main()
{
scanf("%d",&T);
while (T--)
{
scanf("%s",ch);
int L=strlen(ch);
int j=0,p=0;
ne[0]=L;
for (int i=1;i<L;i++)
{
if (i>=j || i+ne[i-p]>=j)
{
if (i>=j) j=i;
while (j<L && ch[j]==ch[j-i]) j++;
ne[i]=j-i;
p=i;
}
else ne[i]=ne[i-p];
}
LL ans=0;
for (int i=1;i<L;i++)
{
ans+=(LL)ne[i];
if (i+ne[i]<L) ans++;
}
printf("%lld\n",ans);
}
return 0;
}
permutation 2
#include<iostream>
using namespace std;
int f[500006]={0,1,1,1},t,n,a,b;
int main(void){
cin>>t;
for(int i=4;i<=100000;i++)f[i]=f[i-1]+f[i-3],f[i]%=998244353;
while(t--){
cin>>n>>a>>b;
if(a>b)swap(a,b);
if(a!=1&&b!=n)cout<<f[b-a-1]<<endl;
else if(a==1&&b==n)cout<<f[n]<<endl;
else cout<<f[b-a]<<endl;
}
}