Intercambiar palabras de esquina e invertir caracteres intermedios

Escriba un programa Java para tomar una string de entrada e intercambiar la primera y la última palabra e invertir la palabra del medio.

Ejemplos: 

Input : Hello World GFG Welcomes You
Output :You semocleW GFG dlroW Hello

Acercarse:  

• Primero tomamos dos strings vacías y la primera string toma la primera palabra y la segunda string toma la última palabra
• Cuando iteramos cada palabra, debemos tener cuidado con la variable que apunta a la siguiente palabra además de la última palabra.
• Ahora invertimos la String izquierda en la String dada.
• Después del proceso anterior, primero imprimimos la última palabra y el reverso de las strings izquierdas y luego la primera palabra.

// C++ Program to illustrate the solution
// of above problem
#include <iostream>
using namespace std;
 
void print(string s)
{
         
    // Taking an Empty String
    string fst = "";
    int i = 0;
    for (i = 0; i < s.length();) {
 
        // Iterating from starting index
        // When we get space, loop terminates
        while (s[i] != ' ') {
            fst = fst + s[i];
            i++;
        }
 
        // After getting one Word
        break;
    }
 
    // Taking an Empty String
    string last = "";
    int j = 0;
    for (j = s.length() - 1; j >= i;) {
 
        // Iterating from last index
        // When we get space, loop terminates
        while (s[j] != ' ') {
            last = s[j] + last;
            j--;
        }
 
        // After getting one Word
        break;
    }
 
    // Printing last word
    cout<<last;
    for (int m = j; m >= i; m--) {
 
        // Reversing the left characters
        cout<<s[m];
    }
 
    // Printing the first word
    cout<<fst;
}
 
int main() {
     
    string s = "Hello World GFG Welcomes You";
    print(s);
     
    return 0;
}
 
//This code is contributed by vt_m.

// Java Program to illustrate the solution of above problem
public class ExchangeFirstLastReverseMiddle {
    static void print(String s)
    {
        // Taking an Empty String
        String fst = "";
        int i = 0;
        for (i = 0; i < s.length();) {
 
            // Iterating from starting index
            // When we get space, loop terminates
            while (s.charAt(i) != ' ') {
                fst = fst + s.charAt(i);
                i++;
            }
 
            // After getting one Word
            break;
        }
 
        // Taking an Empty String
        String last = "";
        int j = 0;
        for (j = s.length() - 1; j >= i;) {
 
            // Iterating from last index
            // When we get space, loop terminates
            while (s.charAt(j) != ' ') {
                last = s.charAt(j) + last;
                j--;
            }
 
            // After getting one Word
            break;
        }
 
        // Printing last word
        System.out.print(last);
        for (int m = j; m >= i; m--) {
 
            // Reversing the left characters
            System.out.print(s.charAt(m));
        }
 
        // Printing the first word
        System.out.println(fst);
    }
 
    public static void main(String[] args)
    {
        String s = "Hello World GFG Welcomes You";
        print(s);
    }
}

# Python3 Program to illustrate the solution
# of above problem
def Print(s) :
         
    # Taking an Empty String
    fst = ""
    i = 0
    while(i < len(s)) :
 
        # Iterating from starting index
        # When we get space, loop terminates
        while (s[i] != ' ') :
            fst = fst + s[i]
            i += 1
 
        # After getting one Word
        break
 
    # Taking an Empty String
    last = ""
    j = len(s) - 1
    while(j >= i) :
 
        # Iterating from last index
        # When we get space, loop terminates
        while (s[j] != ' ') :
            last = s[j] + last
            j -= 1
 
        # After getting one Word
        break
 
    # Printing last word
    print(last, end = "")
    m = j
    while m >= i :
       
        # Reversing the left characters
        print(s[m] , end = "")
        m -= 1
 
    # Printing the first word
    print(fst, end = "")
 
# Driver code
s = "Hello World GFG Welcomes You"
Print(s)
 
# This code is contributed by divyeshrabadiya07

// C# Program to illustrate the
//solution of above problem
using System;
 
class ExchangeFirstLastReverseMiddle
{
    static void print(string s)
    {
        // Taking an Empty String
        string fst = "";
        int i = 0;
        for (i = 0; i < s.Length;) {
 
            // Iterating from starting index
            // When we get space, loop terminates
            while (s[i] != ' ')
            {
                fst = fst + s[i];
                i++;
            }
 
            // After getting one Word
            break;
        }
 
        // Taking an Empty String
        string last = "";
        int j = 0;
        for (j = s.Length - 1; j >= i;) {
 
            // Iterating from last index
            // When we get space, loop terminates
            while (s[j] != ' ') {
                last = s[j] + last;
                j--;
            }
 
            // After getting one Word
            break;
        }
 
        // Printing last word
        Console.Write(last);
        for (int m = j; m >= i; m--) {
 
            // Reversing the left characters
            Console.Write(s[m]);
        }
 
        // Printing the first word
        Console.Write(fst);
    }
 
    // Driver code
    public static void Main()
    {
        string s = "Hello World GFG Welcomes You";
        print(s);
    }
}
 
//This code is contributed by vt_m

Producción: 

You semocleW GFG dlroW Hello

 Complejidad de tiempo: O(N ² ) donde N es la longitud de la string

 Espacio Auxiliar: O(1)