2597. 「NOIP2011」选择客栈

#include<algorithm>
#include<bitset>
#include<complex>
#include<deque>
#include<exception>
#include<fstream>
#include<functional>
#include<iomanip>
#include<ios>
#include<iosfwd>
#include<iostream>
#include<istream>
#include<iterator>
#include<limits>
#include<list>
#include<locale>
#include<map>
#include<memory>
#include<new>
#include<numeric>
#include<ostream>
#include<queue>
#include<set>
#include<sstream>
#include<stack>
#include<stdexcept>
#include<streambuf>
#include<string>
#include<typeinfo>
#include<utility>
#include<valarray>
#include<vector>
#include<cstring>
#include<cmath>
#define ll long long
const int N=2e5+5,M=1e6;
using namespace std;
inline ll read(){
    char ch=getchar();ll res=0,f=1;
    while(ch<'0'ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9') res=res*10+ch-'0',ch=getchar();
    return res*f;
}
inline void write(ll zx){
    if(zx<0) zx=-zx,putchar('-');
    if(zx<10) putchar(zx+'0');
    else{
        write(zx/10);
        putchar(zx%10+'0');
    }
}
ll n,m,color,price,now,las[N],h[N],sum[N],ans,p;
int main(){
    n=read();m=read();p=read();
    for(ll i=1;i<=n;i++){
        color=read(),price=read();//读入
        if(price<=p) now=i;//价钱要小于或等于p
        if(now>=las[color]) sum[color]=h[color];//如果比上一个颜色相同的近，直接加上方案数
        ans+=sum[color];//更新ANS
        h[color]++;las[color]=i;//更新LAS和H
    }
    write(ans);putchar('\n');//输出
    return 0;
}