【PTA-训练day7】L2-019 悄悄关注 + L1-027 出租

L2-019 悄悄关注 - 哈希表

PTA | 程序设计类实验辅助教学平台

1、java - 喜闻乐见超时

import java.util.*;
 
public class Main
{
    public static void main(String[] args)
    {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        String[] name=sc.nextLine().split(" ");
        Set st=new HashSet<>();
        for(int i=0;i
        int k=sc.nextInt();
        double sum=0;
        Set res=new TreeSet<>();
        Mapmp=new HashMap<>();
        int temp=k;
        while(k-->0)
        {
            String x=sc.next();
            int t=sc.nextInt();
            mp.put(x,t);
            sum+=t;
        }
        sum/=temp;
        for(Map.Entry x:mp.entrySet())
        {
            if(!st.contains(x.getKey())&&x.getValue()>sum) res.add(x.getKey());
        }
        if(res.size()==0) System.out.print("Bing Mei You");
        else for(String x:res) System.out.println(x);
    }
}

2、c++

#include 
using namespace std;
 
int main()
{
    int n;
    cin>>n;
    setst;
    for(int i=0;i
    {
        string s;
        cin>>s;
        st.insert(s);
    }
    int k,temp;
    double sum=0;
    cin>>k;
    temp=k;
    mapint>mp;
    while(k--)
    {
        string x;
        int t;
        cin>>x>>t;
        mp[x]=t;
        sum+=t;
    }
    sum/=temp;
    setres;
    for(auto x:mp) 
        if(!st.count(x.first)&&x.second>sum) res.insert(x.first);
    if(res.size()==0) cout<<"Bing Mei You";
    else for(auto x:res) cout<
}

L1-027 出租 - 20

PTA | 程序设计类实验辅助教学平台

import java.util.*;
 
public class Main
{
    public static void main(String[] args)
    {
        Scanner sc=new Scanner(System.in);
        String s=sc.next();
        TreeSet st=new TreeSet<>(Comparator.reverseOrder());
        for(int i=0;i
        System.out.print("int[] arr = new int[]{");
        int cnt=0;
        Map mp=new HashMap<>();
        for(char x:st) 
        {
            System.out.print(x);
            mp.put(x,cnt);
            cnt++;
            if(cnt!=st.size()) System.out.print(",");
        }
        System.out.println("};");
        System.out.print("int[] index = new int[]{");
        int res=0;
        for(int i=0;i
        {
            res++;
            System.out.print(mp.get(s.charAt(i)));
            if(res!=s.length()) System.out.print(",");
        }
        System.out.print("};");
    }
}

L1-025 正整数A+B - 15

PTA | 程序设计类实验辅助教学平台

要注意 不能用split按空格分割 

因为有多个空格存在时 比如123 123 kkk

如果按split分割 则就是123+123=246

但正确答案应该是123+？=？

import java.util.*;
 
public class Main
{
    public static void main(String[] args)
    {
        Scanner sc=new Scanner(System.in);
        String s=sc.nextLine();
        String[] a=new String[2];
        a[0]=s.substring(0,s.indexOf(" "));
        a[1]=s.substring(s.indexOf(" ")+1);
        boolean f1=false,f2=false;
        if(isDigit(a[0])) f1=true;
        if(isDigit(a[1])) f2=true;
        if(f1&&f2)
        {
            Integer s1=Integer.parseInt(a[0]);
            Integer s2=Integer.parseInt(a[1]);
            System.out.print(a[0]+" + "+a[1]+" = "+(s1+s2));
        }
        else if(!f1&&f2) System.out.print("? + "+a[1]+" = ?");
        else if(f1&&!f2) System.out.print(a[0]+" + ? = ?");
        else System.out.print("? + ? = ?");
    }
    
    public static boolean isDigit(String s)
    {
        if(s.charAt(0)=='0'||(s.length()>3&&!"1000".equals(s))) return false;
        for(int i=0;i
            if((s.charAt(i)-'0')<0||(s.charAt(i)-'0')>9) 
                return false;
        return true;
    }
}

L1-028 判断素数 - 10

import java.util.*;
 
public class Main
{
    public static void main(String[] args)
    {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        while(n-->0)
        {
            int x=sc.nextInt();
            if(isprime(x)) System.out.println("Yes");
            else System.out.println("No");
        }
    }
    
    public static boolean isprime(int n)
    {
        if(n==0||n==1) return false;
        for(int i=2;i<=n/i;i++) if(n%i==0) return false;
        return true;
    }
}