时间复杂度

参考文献

JAVA 代码

import java.util.Scanner;
import java.util.ArrayList;
import java.util.List;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        List<Integer> list = new ArrayList<>();
        int num = sc.nextInt();
        while(num!=0){
            int t = num%26;
            if(t==0) t = 26;
            num = (num-t)/26;
            list.add(t);
        }
        // list.add(num);
        for(int i = list.size()-1;i>=0;i--){
            System.out.print((char)(list.get(i)+'A'-1));
        }
    }
}

#方法二
import java.util.Scanner;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        StringBuilder sb = new StringBuilder();
        while(n!=0){
            char t = (char)((n-1)%26 + 'A');
            sb.append(t);
            n = (n-1)/26;
        }
        System.out.println(sb.reverse().toString());
    }
}