我的问题在于排列类，我有两个int数组，例如 在排列类的主要部分。 我必须检查堆栈提供的操作是否可以进行这种排列... push，pop，isEmpty，top ....
我被卡住了，方法switchValues（）需要通过我找不到解决方案来纠正...请帮帮忙。 THX
public class Permutation {
private Stack _permStack;
private int [] _beforePerm;
private int [] _afterPerm;
private int _beforeIndex =0;
private int _afterIndex = 0;
public Permutation (int [] beforePerm, int [] afterPerm){
_beforePerm = beforePerm;
_afterPerm = afterPerm;
_permStack = new Stack (10);
}
public boolean arrayPreCheck(){
boolean reversedArray= false;
for (int i=0; i<_beforePerm.length-1;i++){
for (int j = _afterPerm.length-1; j >0;j--){
if (_beforePerm[i] ==_afterPerm[j]){
reversedArray = true;
}else{
return reversedArray = false;
}
}
}
return reversedArray;
}
public boolean isPermutation(){
if(_permStack.isEmpty()&&_beforeIndex ==_beforePerm.length&&_afterIndex ==_afterPerm.length){
System.out.println("Permutation is true");
return true;
}else{
return false;
}
}
public void switchValues(){
_permStack.push(_beforePerm[_beforeIndex]);
while(!isPermutation()&& _beforeIndex <_beforePerm.length){
if(_permStack.top() == _afterPerm[_afterIndex]){
_permStack.pop();
_beforeIndex++;
_afterIndex++;
if(_beforeIndex < _beforePerm.length){
_permStack.push(_beforePerm[_beforeIndex]);
}
}else{
_beforeIndex++;
if(_beforeIndex < _beforePerm.length){
_permStack.push(_beforePerm[_beforeIndex]);
}
}
}
if(!isPermutation()){
System.out.println("Permutation false");
}
}
public static void main (String []args){
int [] before = new int[] {1,2,3,4,5};
int [] after = new int []{1,3,5,4,2};
Permutation myPerm = new Permutation (before,after);
myPerm.switchValues();
}
}
class Stack {
private int [] _values;
private int _position;
public Stack (int size){
_values = new int [size];
_position = 0;
}
public boolean isEmpty(){
if (_position == 0){
return true;
}else{
return false;
}
}
public int top(){
if(isEmpty()){
return -1;
}else{
return _values[_position-1];
}
}
public boolean push(int value){
if (_position< _values.length){
_values [_position] = value;
_position++;
System.out.println("push:"+value);
return true;
}else{
return false;
}
}
public int pop(){
if (isEmpty()){
return -1;
}else{
_position--;
System.out.println("pop: "+ _values[_position]);
return _values[_position];
}
}
public void printStack(){
int j = 0;
for (int i=0;i<_values.length;i++){
System.out.println(_values[i]+" at the spot: "+ j);
j++;
}
}