2-21算法习题总结

由于蓝桥杯的题,我不知道从怎么复制,就只能粘贴图片了

翻硬币

代码

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String start = sc.next();
        char[] starts = start.toCharArray();
        String end = sc.next();
        char[] ends = end.toCharArray();
        int count=0;
        for (int i = 0; i < starts.length; i++) {
            if(starts[i]!=ends[i]){
                starts[i]=starts[i]=='*'?'o':'*';
                starts[i+1]=starts[i+1]=='*'?'o':'*';
                count++;
            }else {
                continue;
            }
        }
        System.out.println(count);
    }
}


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错误票据

代码

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        List<Integer> list = new ArrayList<>();
        while (sc.hasNext()){
            list.add(sc.nextInt());
        }
        Collections.sort(list);
        int m = 0;
        int n = 0;
        for (int i = 1; i < list.size(); i++) {
            if (list.get(i).equals(list.get(i - 1))) {
                m = list.get(i);
            }else if(list.get(i)-list.get(i - 1)==2){
                n=list.get(i-1)+1;
            }
        }
        System.out.println(n+" "+m);
    }
}

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总结

读取未知个数的数据时,有两种形式

1.     public static void main(String[] args) {
           Scanner sc = new Scanner(System.in);
           int N = sc.nextInt();
           List<Integer> list = new ArrayList<>();
           while (sc.hasNext()){
               list.add(sc.nextInt());
           }
       } } ```
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2.     public static void main(String[] args) {
           Scanner scanner = new Scanner(System.in);
           int N = scanner.nextInt();
           scanner.nextLine();
           ArrayList<Integer> record = new ArrayList<>();
           for (int i = 0; i < N; i++) {
               for (String s : scanner.nextLine().split(" ")) {
                   record.add(Integer.valueOf(s));
               }
           }
       } } ``
   
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