[Luogu 3901]Difference

Description

Input

Output

Sample Input

4 2
1 2 3 2
1 3
2 4

Sample Output

Yes
No

HINT

题解

莫队。加个标记数组维护该数在区间中出现了几次，再加个变量统计有几个数是重复的。

#include<map>
#include<set>
#include<ctime>
#include<cmath>
#include<queue>
#include<stack>
#include<cstdio>
#include<string>
#include<vector>
#include<cstdlib>
#include<cstring>
#include<iostream>
#include<algorithm>
#define LL long long
#define RE register
#define IL inline
using namespace std;
const int N=1e5;

int n,q,lim;
int cnt[N+5],a[N+5];
struct tt
{
    int l,r,id;
}query[N+5];
bool keep[N+5];

IL bool comp(const tt &a,const tt &b) {return a.l/lim==b.l/lim ? a.r<b.r : a.l<b.l;}

int main()
{
    scanf("%d%d",&n,&q);
    lim=sqrt(n);
    for (RE int i=1;i<=n;i++) scanf("%d",&a[i]);
    for (RE int i=1;i<=q;i++) scanf("%d%d",&query[i].l,&query[i].r),query[i].id=i;
    sort(query+1,query+1+q,comp);
    int curl=1,curr=0,ans=0,l,r;
    for (RE int i=1;i<=q;i++)
    {
        l=query[i].l,r=query[i].r;
        while (curl<l) cnt[a[curl]]--,ans-=(cnt[a[curl++]]==1);
        while (curl>l) cnt[a[--curl]]++,ans+=(cnt[a[curl]]==2);
        while (curr<r) cnt[a[++curr]]++,ans+=(cnt[a[curr]]==2);
        while (curr>r) cnt[a[curr]]--,ans-=(cnt[a[curr--]]==1);
        if (!ans) keep[query[i].id]=1;
    }
    for (RE int i=1;i<=q;i++) printf(keep[i] ? "Yes
":"No
");
    return 0;
}