蓝桥杯基础-013-Palindrome_Special_Number

题意

输入一个数字n

输出一个五位或六位回文数 && 各位数字和为n

代码

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner keyin = new Scanner(System.in);
		int n = keyin.nextInt();
		int result = 0;
		for (int i = 0; i < 10; i++) {
			boolean digit5 = false;
			for (int j = 0; j < 10; j++) {
				if(i == 0){
					digit5 = true;
					if( j == 0) continue;
				}
				for (int j2 = 0; j2 < 10; j2++) {
					for (int k = 0; k < 10; k++) {
						for (int k2 = 0; k2 < 10; k2++) {
							for (int l = 0; l < 10; l++) {
								if(digit5){
									if(j == l && j2 == k2 && n == j+j2+k+k2+l){
										result = j*10000 + j2*1000 + k*100 + k2*10 + l;
										System.out.println(result);
									}
								}
								else{
									if(i == l && j == k2 && j2 == k && n == i+j+j2+k+k2+l){
										result = i*100000 + j*10000 + j2*1000 + k*100 + k2*10 + l;
										System.out.println(result);
									}

								}
							}
						}
					}
				}
			}
		}

	}

}

Summary

1.五层循环 每层都是 0 to 9 + 特殊（第一层为0时,若第二层也为0 -> continue; else digit5 process ）else digit6 process 

2.一层循环 10000 to 999999 + if digit5 else digit6 + MOD & / 取出各位操作