Laptop 题解

首先我们先对笔记本的内存进行排序，记得同时交换速度的位置。
然后我们从后往前遍历内存，同时记录后k项的最大值max,如果当前速度小于max,就说明完败与一台笔记本。
最后记录个数即可.

import java.math.*;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.StreamTokenizer;
import java.util.*;
public class Main {
    public static void main(String args[])throws IOException
    {
        StreamTokenizer in = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
        PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
        in.nextToken();
        int n = (int)in.nval;
        int m[] = new int[n];
        int s[] = new int[n];
        int max[] = new int[n];
        for(int i=0;i<n;i++)
        {
            in.nextToken();
            m[i] = (int)in.nval;
            in.nextToken();
            s[i] = (int)in.nval;
        }
        quickSort(0,n-1,m,s);
        int maxs=0,sum=0;
        for(int i=n-1;i>=0;i--)
        {
            if(s[i]>maxs)
            {
                maxs = s[i];
            }
            else
            {
                sum++;
            }
        }
        out.print(sum);
        out.flush();
    }
    public static void quickSort(int l,int r,int m[],int s[])
    {
        int i=l,j=r,key=m[(l+r)>>1],temp,temps;
        do{
            while(m[i]<key) i++;
            while(m[j]>key) j--;
            if(i<=j)
            {
                temp = m[i];
                m[i] = m[j];
                m[j] = temp;
                temps = s[i];
                s[i] = s[j];
                s[j] = temps;
                i++;
                j--;
            }
        }while(i<=j);
        if(i<r) quickSort(i,r,m,s);
        if(l<j) quickSort(l,j,m,s);
    }
                  }