版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/YewSpadeJ/article/details/81908363
//普通莫队板子
#include<iostream>
#include<cstdio>
#include<cmath>
#include<algorithm>
#define maxn 30005
#define maxm 30005
#define maxnum 30005
using namespace std;
int leftt,rightt,n,m,k,anss,block;
int a[maxn],numm[maxnum], bl[maxn], ans[maxn];
struct Ask
{
int l,r,num;
}ask[maxm];
bool cmp(Ask x,Ask y)
{
return bl[x.l] != bl[y.l] ? x.l < y.l : x.r < y.r;
}
void remove_num(int stu)
{
if(numm[a[stu]]==k)
anss--;
numm[a[stu]]--;
if(numm[a[stu]]==k)
anss++;
return;
}
void add_num(int stu)
{
if(numm[a[stu]]==k)
anss--;
numm[a[stu]]++;
if(numm[a[stu]]==k)
anss++;
return;
}
void deal(int L,int R,int ord)
{
while(1)
{
if(leftt<L)remove_num(leftt++);
if(leftt>L)add_num(--leftt);
if(rightt<R)add_num(++rightt);
if(rightt>R)remove_num(rightt--);
if(L==leftt&&R==rightt)
{ans[ask[ord].num]=anss;break;}
}
return;
}
int main()
{
cin>>n>>k>>m;
block=sqrt(n);
for(int i=1;i<=n;i++)
cin>>a[i], bl[i] = (i - 1)/block + 1;
for(int i=1;i<=m;i++)
{cin>>ask[i].l>>ask[i].r;ask[i].num=i;}
sort(ask + 1, ask + 1 + m, cmp);
for(int i=1;i<=m;i++)
deal(ask[i].l,ask[i].r,i);
for(int i=1;i<=m;i++)
printf("%d\n", ans[i]);
return 0;
}