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这题没什么话说。

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#define maxn 200500
using namespace std;
int n,k,p,pos[][maxn],cnt[maxn],r[maxn],col[maxn],val[maxn],pre[maxn],regis=;
long long ans=;
int ask(int col,int poss)
{
    int l=,r=cnt[col],ans=;
    while (l<=r)
    {
        int mid=(l+r)>>;
        if (pos[col][mid]<=poss) {ans=mid;l=mid+;}
        else r=mid-;
    }
    return pos[col][ans];
}
int main()
{
    scanf("%d%d%d",&n,&k,&p);
    for (int i=;i<=n;i++)
        scanf("%d%d",&col[i],&val[i]);
    for (int i=;i<=n;i++)
    {
        pos[col[i]][++cnt[col[i]]]=i;
        r[i]=cnt[col[i]];
        if (val[i]<=p) regis=i;
        pre[i]=regis;
    }
    for (int i=;i<=n;i++)
    {
        if (r[i]==) continue;
        if (pre[i]==i) ans+=r[i]-;
        else
            ans+=r[ask(col[i],pre[i])];
    }
    printf("%lld\n",ans);
    return ;
}