网易笔试

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNext()) {
            int n=in.nextInt();
            int[] nums=new int[n];
            for(int i=0;i<n;i++){
                nums[i]=in.nextInt();
            }
            System.out.println(circle(nums,n));
        }
        in.close();
    }
//    public boolean iscircle(int[] nums,int n){
//        int j=0;
//        while(j<=(n/2)-1&&nums[j]==nums[n-j-1])
//            j++;
//        if(j==n/2)
//            return true;
//        else
//            return false;
//    }
    public static int circle(int[] nums,int n){
        int count=0;
        List<Integer> list=new ArrayList<Integer>();
        int i=0;
        for (int num:nums){
            list.add(i,num);
            i++;
        }
        for(int j=0;j<=(n+1)/2-1;j++){
            if(list.get(j)==list.get(n-j-1))
                continue;
            else{
                int a=list.get(j)+list.get(j+1);
                list.set(j,a);
                list.remove(j+1);
                n--;
                count++;
                j--;
            }
        }
        return count;
    }
}

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNext()) {
            int n=in.nextInt();
            int res=caculate(n);
            System.out.println(res);
        }
        in.close();
    }

    private static int caculate(int n) {
        int res=0;
        if(n<=0)
           return 0;
        if(n==1){
            return 3;
        }
        if(n==2)
            return 9;
        res=2*caculate(n-1)+caculate(n-2);
        return res;
    }
}

import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNext()) {
            String x = String.valueOf(in.nextInt());
            StringBuffer a=new StringBuffer(x);
            a=a.reverse();
            String y = String.valueOf(in.nextInt());
            StringBuffer b=new StringBuffer(y);
            b=b.reverse();
            int c=Integer.parseInt(String.valueOf(a))+Integer.parseInt(String.valueOf(b));
            StringBuffer d=new StringBuffer(String.valueOf(c));
            System.out.println(Integer.parseInt(String.valueOf(d.reverse())));
        }
    }
}