[Luogu 3901]Difference

Posted 2020-10-02 NaVi_Awson

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。

 

 1 #include<map>
 2 #include<set>
 3 #include<ctime>
 4 #include<cmath>
 5 #include<queue>
 6 #include<stack>
 7 #include<cstdio>
 8 #include<string>
 9 #include<vector>
10 #include<cstdlib>
11 #include<cstring>
12 #include<iostream>
13 #include<algorithm>
14 #define LL long long
15 #define RE register
16 #define IL inline
17 using namespace std;
18 const int N=1e5;
19 
20 int n,q,lim;
21 int cnt[N+5],a[N+5];
22 struct tt
23 {
24     int l,r,id;
25 }query[N+5];
26 bool keep[N+5];
27 
28 IL bool comp(const tt &a,const tt &b) {return a.l/lim==b.l/lim ? a.r<b.r : a.l<b.l;}
29 
30 int main()
31 {
32     scanf("%d%d",&n,&q);
33     lim=sqrt(n);
34     for (RE int i=1;i<=n;i++) scanf("%d",&a[i]);
35     for (RE int i=1;i<=q;i++) scanf("%d%d",&query[i].l,&query[i].r),query[i].id=i;
36     sort(query+1,query+1+q,comp);
37     int curl=1,curr=0,ans=0,l,r;
38     for (RE int i=1;i<=q;i++)
39     {
40         l=query[i].l,r=query[i].r;
41         while (curl<l) cnt[a[curl]]--,ans-=(cnt[a[curl++]]==1);
42         while (curl>l) cnt[a[--curl]]++,ans+=(cnt[a[curl]]==2);
43         while (curr<r) cnt[a[++curr]]++,ans+=(cnt[a[curr]]==2);
44         while (curr>r) cnt[a[curr]]--,ans-=(cnt[a[curr--]]==1);
45         if (!ans) keep[query[i].id]=1;
46     }
47     for (RE int i=1;i<=q;i++) printf(keep[i] ? "Yes\\n":"No\\n");
48     return 0;
49 }