從尾到頭打印鏈表

題目：輸入個(gè)鏈表的頭結(jié)點(diǎn)，從尾到頭反過(guò)來(lái)打印出每個(gè)結(jié)點(diǎn)的值。

[java] view plaincopyprint?
public class Test05 {  
    /** 
     * 結(jié)點(diǎn)對(duì)象 
     */  
    public static class ListNode {  
        int val; // 結(jié)點(diǎn)的值  
        ListNode nxt; // 下一個(gè)結(jié)點(diǎn)  
    }  
    /** 
     * 輸入個(gè)鏈表的頭結(jié)點(diǎn)，從尾到頭反過(guò)來(lái)打印出每個(gè)結(jié)點(diǎn)的值 
     * 使用棧的方式進(jìn)行 
     * 
     * @param root 鏈表頭結(jié)點(diǎn) 
     */  
    public static void printListInverselyUsingIteration(ListNode root) {  
        Stack<ListNode> stack = new Stack<>();  
        while (root != null) {  
            stack.push(root);  
            root = root.nxt;  
        }  
        ListNode tmp;  
        while (!stack.isEmpty()) {  
            tmp = stack.pop();  
            System.out.print(tmp.val + " ");  
        }  
    }  
    /** 
     * 輸入個(gè)鏈表的頭結(jié)點(diǎn)，從尾到頭反過(guò)來(lái)打印出每個(gè)結(jié)點(diǎn)的值 
     * 使用棧的方式進(jìn)行 
     * 
     * @param root 鏈表頭結(jié)點(diǎn) 
     */  
    public static void printListInverselyUsingRecursion(ListNode root) {  
        if (root != null) {  
            printListInverselyUsingRecursion(root.nxt);  
            System.out.print(root.val + " ");  
        }  
    }  
    public static void main(String[] args) {  
        ListNode root = new ListNode();  
        root.val = 1;  
        root.nxt = new ListNode();  
        root.nxt.val = 2;  
        root.nxt.nxt = new ListNode();  
        root.nxt.nxt.val = 3;  
        root.nxt.nxt.nxt = new ListNode();  
        root.nxt.nxt.nxt.val = 4;  
        root.nxt.nxt.nxt.nxt = new ListNode();  
        root.nxt.nxt.nxt.nxt.val = 5;  
        printListInverselyUsingIteration(root);  
        System.out.println();  
        printListInverselyUsingRecursion(root);  
    }  
}  

運(yùn)行結(jié)果：

http://wiki.jikexueyuan.com/project/for-offer/images/4.png" alt="" />