題目描述:輸入兩個整數序列,第一個序列表示棧的壓入順序,請判斷第二個序列是否爲該棧的彈出順序。假設壓入棧的所有數字均不相等。例如序列1,2,3,4,5是某棧的壓入順序,序列4,5,3,2,1是該壓棧序列對應的一個彈出序列,但4,3,5,1,2就不可能是該壓棧序列的彈出序列。(注意:這兩個序列的長度是相等的)
package swordRefersToOffer;
import java.util.Scanner;
import java.util.Stack;
public class IsPopOrder {
public static void main(String[] args){
int[] n2 = new int[]{1,2,3,4,5};
int[] n1 = new int[]{5,4,3,2,1};
System.out.println(IsPopOrder1(n2,n1));
}
public static boolean IsPopOrder1(int [] pushA,int [] popA) {
if(popA.length == 0){
return false;
}
Stack<Integer> stack = new Stack<Integer>();
int j = 0;
for(int i = 0; i < popA.length;i++){
stack.push(pushA[i]);
while(j<popA.length && stack.peek() == popA[j]){
stack.pop();
j++;
}
}
return stack.empty() ? true : false;
}
}