反转表示为链接列表的字符串中的所有单词

给定一个表示句子 S 的链表，其中每个节点代表一个字母，任务是在不反转单个单词的情况下反转句子。
例如，对于给定的句子“I love Geeks for Geeks”，链表表示为：
I->->l->o->v->e->->G->e->e->k->s->->f->o->r->->G-> e->e->k->s

例子：

Input: I love Geeks for Geeks 
Output: Geeks for Geeks love I

Input: practice makes a man perfect 
Output: perfect man a makes practice 

方法：这个想法是从头开始导航链表。每次遇到空格时，将空格交换到该单词的开头。重复此步骤，直到到达最后一个节点。最后将第一个单词最后一个字母设置为指向 null ，它将成为最后一个节点并不断更改指针。

下面是该方法的实现：

Java

// Linked List Implementation
public class Node {
    public Node(char data, Node next)
    {
        Data = data;
        Next = next;
    }
    public char Data;
    public Node Next;
}
class GFG {
 
    // Function to create a linked list
    // from the given String
    private static Node CreateLinkedList(String s)
    {
        Node header = null;
        Node temp = null;
        // Generates characters from the given string
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);
            Node node = new Node(c, null);
 
            if (header == null) {
                header = node;
                temp = header;
            }
            else {
                temp.Next = node;
                temp = temp.Next;
            }
        }
        return header;
    }
 
    // Function to reverse the words
    // Assume str = "practice makes man perfect"
    // to understand proper understanding of the code
    private static Node Reverse(Node header)
    {
        if (header == null)
            return header;
 
        Node wordStartPosition = null;
        Node endOfSentence = null;
        Node sentenceStartPosition = null;
 
        // Initialize wordStartPosition to header
        // ie. node 'p' first letter of the word 'practice'
        wordStartPosition = header;
 
        // Navigate the linked list until
        // a space(' ') is found or header is null
        //(this is for handing if there is
        // only one word in the given sentence)
        while (header != null && header.Data != ' ') {
 
            // Keep track the previous node.
            // This will become the
            // last node of the linked list
            endOfSentence = header;
 
            // Keep moving to the next node
            header = header.Next;
        }
 
        // After the above while loop,
        // endOfSentence points to
        // the last letter 'e'of word 'practice'
        // header points to the space(' ')
        // which is next to word 'practice'
 
        // If header is null then there is only
        // one word in the given sentence
        // so set header to the
        // first/wordStartPosition node and return.
        if (header == null) {
            header = wordStartPosition;
            return header;
        }
 
        do {
 
            // Swapping the space ie.
            // convert 'practice' to
            //'practice'
 
            // store the node which is next to space(' ')
            // 'm' which is the first letter of the word 'make'
            Node temp = header.Next;
            header.Next = wordStartPosition;
            wordStartPosition = header;
            header = temp;
 
            Node prev = null;
            // Setting sentenceStartPosition to node 'm'
            //(first letter of the word 'make')
            sentenceStartPosition = header;
 
            // Again Navigate the linked list until
            // a space(' ') is found or
            // header == null end of the linked list
            while (header != null && header.Data != ' ') {
                prev = header;
                header = header.Next;
            }
 
            // When the next space is found,
            // change the pointer to point the previous space
            // ie. the word is being converted to
            // "m->a->k->e->s-> ->p->r->a->c->t->i->c->e"
            prev.Next = wordStartPosition;
 
            // Newly found space will point to
            //'m' first letter of the word 'make'
            wordStartPosition = sentenceStartPosition;
            if (header == null)
                break;
 
            // Repeat the loop until
            // the end of the linked list is reached
        } while (header != null);
 
        header = sentenceStartPosition;
 
        // Set the last node's next to null
        // ie. ->m->a->k->e->s-> ->p->r->a->->c->t->i->c->e->null
        endOfSentence.Next = null;
        return header;
    }
 
    // Function to print the Linked List
    private static void PrintList(Node Header)
    {
        Node temp = Header;
        // Navigate till the end and print the data in each node
        while (temp != null) {
            System.out.print(temp.Data);
            temp = temp.Next;
        }
    }
 
    // Driver code
    public static void main(String[] args)
    {
        String s = "practice makes a man perfect";
 
        // Convert given string to a linked list
        // with character as data in each node
        Node header = CreateLinkedList(s);
 
        System.out.println("Before:");
        PrintList(header);
 
        header = Reverse(header);
 
        System.out.println("\nAfter:");
        PrintList(header);
    }
}

C#

using System;
 
// Linked List Implementation
public class Node
{
    public Node(char data, Node next)
    {
        Data = data;
        Next = next;
    }
    public char Data;
    public Node Next;
}
 
class GFG
{
 
    // Function to create a linked list
    // from the given String
    private static Node CreateList(String s)
    {
        Node header = null;
        Node temp = null;
         
        // Generates characters from the given string
        for (int i = 0; i < s.Length; i++)
        {
            char c = s[i];
            Node node = new Node(c, null);
 
            if (header == null)
            {
                header = node;
                temp = header;
            }
            else
            {
                temp.Next = node;
                temp = temp.Next;
            }
        }
        return header;
    }
 
    // Function to reverse the words
    // Assume str = "practice makes man perfect"
    // to understand proper understanding of the code
    private static Node Reverse(Node header)
    {
        if (header == null)
            return header;
 
        Node wordStartPosition = null;
        Node endOfSentence = null;
        Node sentenceStartPosition = null;
 
        // Initialize wordStartPosition to header
        // ie. node 'p' first letter of the word 'practice'
        wordStartPosition = header;
 
        // Navigate the linked list until
        // a space(' ') is found or header is null
        //(this is for handing if there is
        // only one word in the given sentence)
        while (header != null && header.Data != ' ')
        {
 
            // Keep track the previous node.
            // This will become the
            // last node of the linked list
            endOfSentence = header;
 
            // Keep moving to the next node
            header = header.Next;
        }
 
        // After the above while loop,
        // endOfSentence points to
        // the last letter 'e'of word 'practice'
        // header points to the space(' ')
        // which is next to word 'practice'
 
        // If header is null then there is only
        // one word in the given sentance
        // so set header to the
        // first/wordStartPosition node and return.
        if (header == null)
        {
            header = wordStartPosition;
            return header;
        }
 
        do
        {
 
            // Swapping the space ie.
            // convert 'practice' to
            //'practice'
 
            // store the node which is next to space(' ')
            // 'm' which is the first letter of the word 'make'
            Node temp = header.Next;
            header.Next = wordStartPosition;
            wordStartPosition = header;
            header = temp;
 
            Node prev = null;
             
            // Setting sentenceStartPosition to node 'm'
            //(first letter of the word 'make')
            sentenceStartPosition = header;
 
            // Again Navigate the linked list until
            // a space(' ') is found or
            // header == null end of the linked list
            while (header != null && header.Data != ' ')
            {
                prev = header;
                header = header.Next;
            }
 
            // When the next space is found,
            // change the pointer to point the previous space
            // ie. the word is being converted to
            // "m->a->k->e->s-> ->p->r->a->c->t->i->c->e"
            prev.Next = wordStartPosition;
 
            // Newly found space will point to
            //'m' first letter of the word 'make'
            wordStartPosition = sentenceStartPosition;
            if (header == null)
                break;
 
            // Repeat the loop until
            // the end of the linked list is reached
        }
         
        while (header != null);
        header = sentenceStartPosition;
 
        // Set the last node's next to null
        // ie. ->m->a->k->e->s-> ->p->r->a->->c->t->i->c->e->null
        endOfSentence.Next = null;
        return header;
    }
 
    // Function to print the Linked List
    private static void PrintList(Node Header)
    {
        Node temp = Header;
         
        // Navigate till the end and print
        // the data in each node
        while (temp != null)
        {
            Console.Write(temp.Data);
            temp = temp.Next;
        }
    }
 
    // Driver code
    public static void Main(String[] args)
    {
        String s = "practice makes a man perfect";
 
        // Convert given string to a linked list
        // with character as data in each node
        Node header = CreateList(s);
 
        Console.WriteLine("Before:");
        PrintList(header);
 
        header = Reverse(header);
 
        Console.WriteLine("\nAfter:");
        PrintList(header);
    }
}
 
// This code is contributed by Rajput-Ji

输出：

Before:
practice makes a man perfect
After:
perfect man a makes practice