P4396 [AHOI2013] 作业

经典的莫队+值域分块
虽然直接用莫队+树状数组也是能过的

贴个板子

#include<algorithm>
#include<cstdio>
#include<cstring>
#include<vector>
#include<queue>
#include<map>
#include<cmath>
#define fo(i,a,b) for (int (i)=(a);(i)<=(b);(i)++)
#define fd(i,b,a) for (int (i)=(b);(i)>=(a);(i)--)
#define mk(x,y) make_pair((x),(y))
//#define A puts("YES")
//#define B puts("NO")
using namespace std;
typedef long long ll;
typedef double db;
const ll inf=1ll<<60;
const int N=1e5+5;
int S,t;
struct node{
	int l,r,a,b,id;
	bool operator < (const node &x) const{
		if (l/S !=x.l/S) return l<x.l;
		return (l/S) &1 ? r<x.r : r>x.r;
	}
};
node q[N];
int n,m,c[N],L[N],R[N],pos[N];
int a[N],b[N],l,r,p,cnt[N];

struct key{
	int a,b;
};
key ans[N];

void add(int x){
	p=pos[x];
	cnt[x]++;
	
	a[p]++;
	if (cnt[x]==1) b[p]++;
}
void sub(int x){
	p=pos[x];
	cnt[x]--;
	a[p]--;
	if (!cnt[x]) b[p]--;
}
void ask(int l,int r,int id){
	int p=pos[l],q=pos[r];
	int s1=0,s2=0;
	if (p==q) {
		fo(i,l,r) {
			s1+=cnt[i];
			s2+=cnt[i]>0;
		}
		ans[id]=(key){s1,s2};
		return;
	}
	
	fo(i,p+1,q-1) {
		s1+=a[i]; 
		s2+=b[i];
	}
	fo(i,l,R[p]){
		s1+=cnt[i];
		s2+=cnt[i]>0;
	}
	fo(i,L[q],r) {
		s1+=cnt[i];
		s2+=cnt[i]>0;
	}
	ans[id]=(key){s1,s2};
}
int main(){
//	freopen("data.in","r",stdin);    	
	
	scanf("%d %d",&n,&m);
	S=sqrt(n);
	fo(i,1,n) scanf("%d",&c[i]);
	
	fo(i,1,m){
		scanf("%d %d %d %d",&q[i].l, &q[i].r, &q[i].a, &q[i].b);
		q[i].id=i;
	}
	sort(q+1,q+m+1);
	
	t=sqrt(N-1);
	fo(i,1,t) {
		L[i]=(i-1)*t+1;
		R[i]=i*t;
	}
	if (R[t]<N-1) t++, L[t]=R[t-1]+1,R[t]=N-1;
	
	fo(i,1,t) {
		fo(j,L[i],R[i]) {
			pos[j]=i;
		}
	}
	
	l=1; r=0;
	fo(i,1,m) {
		while (l>q[i].l) add(c[--l]);
		while (r<q[i].r) add(c[++r]);
		while (l<q[i].l) sub(c[l++]);
		while (r>q[i].r) sub(c[r--]);
		
		ask(q[i].a, q[i].b, q[i].id);
	}
	
	fo(i,1,m) printf("%d %d\n",ans[i].a ,ans[i].b);
	
	return 0;
	
}