/*
* Created on 13-3-4
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*
* Copyright @2013 the original author or authors.
*/
package ch08algorithm;
/**
* 九连环
*
* @author XiongNeng
* @version 1.0
* @since 13-3-4
*/
public class NineCircles {
private static final int CIRCLE_NUM = 9;
private static int upCount = 0;
private static int downCount = 0;
public static void main(String[] args) {
mockNineCircle(CIRCLE_NUM);
//mockNineCircle(new int[]{0, 0, 0}, new int[]{1, 1, 1});
}
private static void mockNineCircle(int circleNum) {
int[] statusOff = new int[circleNum];
int[] statusOn = new int[circleNum];
for (int i = 0; i < circleNum; i++) {
statusOff[i] = 0;
statusOn[i] = 1;
}
System.out.println("----上环----START");
UP(statusOff, statusOff.length);
System.out.println("上环总步骤数：" + upCount);
System.out.println("----------END---------");
System.out.println("----下环----START");
DOWN(statusOn, statusOn.length);
System.out.println("下环总步骤数：" + downCount);
System.out.println("--------END------------");
}
private static void mockNineCircle(int[] statusOff, int[] statusOn) {
System.out.println("----上环----START");
UP(statusOff, statusOff.length);
System.out.println("上环总步骤数：" + upCount);
System.out.println("----------END---------");
System.out.println("----下环----START");
DOWN(statusOn, statusOn.length);
System.out.println("下环总步骤数：" + downCount);
System.out.println("--------END------------");
}
/**
* 上环一个
*
* @param status
* @param index
*/
private static void up(int[] status, int index) {
if (index <= 0) return;
if (index == 1) {
justUp(status, 1);
} else if (isAllOff(status, index - 2) && isOn(status, index - 1)) {
justUp(status, index);
} else {
if (!isOn(status, index - 1)) up(status, index - 1);
if (!isAllOff(status, index - 2)) DOWN(status, index - 2);
justUp(status, index);
}
}
/**
* 下环一个
*
* @param status
* @param index
*/
private static void down(int[] status, int index) {
if (index <= 0) return;
if (index == 1) {
justDown(status, index);
} else if (isAllOff(status, index - 2) && isOn(status, index - 1)) {
justDown(status, index);
} else {
if (!isOn(status, index - 1)) up(status, index - 1);
if (!isAllOff(status, index - 2)) DOWN(status, index - 2);
justDown(status, index);
}
}
/**
* 上环前number个
*
* @param status
* @param number
*/
private static void UP(int[] status, int number) {
if (number == 1) {
justUp(status, 1);
} else if (number == 2) {
justUp(status, 1);
justUp(status, 2);
} else if (number > 2) {
if (!isOn(status, number - 1)) up(status, number - 1);
if (!isAllOff(status, number - 2)) {
int validNum = number - 2;
while (validNum > 0) {
if (status[validNum - 1] == 1) {
break;
}
validNum--;
}
DOWN(status, validNum);
}
if (!isOn(status, number)) up(status, number);
if (!isAllOn(status, number - 1)) {
int validNum = number - 1;
while (validNum > 0) {
if (status[validNum - 1] == 0) {
break;
}
validNum--;
}
UP(status, validNum);
}
}
}
/**
* 下环前number个
*
* @param status
* @param number
*/
private static void DOWN(int[] status, int number) {
if (number == 1) {
justDown(status, 1);
} else if (number == 2) {
justUp(status, 1);
justDown(status, 2);
justDown(status, 1);
} else if (number > 2) {
if (!isOn(status, number - 1)) up(status, number - 1);
if (!isAllOff(status, number - 2)) DOWN(status, number - 2);
if (!isOff(status, number)) down(status, number);
if (!isAllOff(status, number - 1)) DOWN(status, number - 1);
}
}
private static void justUp(int[] status, int index) {
if (status[index - 1] == 0) {
for (int k : status) System.out.print(k);
System.out.println();
System.out.println("----上环：" + index);
status[index - 1] = 1;
upCount++;
}
}
private static void justDown(int[] status, int index) {
if (status[index - 1] == 1) {
for (int k : status) System.out.print(k);
System.out.println();
System.out.println("----下环：" + index);
status[index - 1] = 0;
downCount++;
}
}
/**
* 数组arr前num个数是否都是1
*
* @param arr
* @param num
* @return
*/
private static boolean isAllOn(int[] arr, int num) {
if (num <= 0) return true;
boolean isAllOn = true;
for (int i = 0; i < num; i++) {
if (arr[i] == 0) {
isAllOn = false;
break;
}
}
return isAllOn;
}
private static boolean isOn(int[] arr, int num) {
return num <= 0 || arr[num - 1] == 1;
}
private static boolean isOff(int[] arr, int num) {
return num <= 0 || arr[num - 1] == 0;
}
/**
* 数组arr前num个数是否都是0
*
* @param arr
* @param num
* @return
*/
private static boolean isAllOff(int[] arr, int num) {
if (num <= 0) return true;
boolean isAllOff = true;
for (int i = 0; i < num; i++) {
if (arr[i] == 1) {
isAllOff = false;
break;
}
}
return isAllOff;
}
}