Question

recursively take two strings that are NOT THE SAME and return the string that consists of all the letters that appear in both string1 and string2 using only string1 and string2 as inputs with NO LOOPS. This must be done recursively.

for example, if string1 is "fourth" and string2 is "faster" the string returned is "frt"

Answer 1

Please let me know if anything is required. I have completed this code in python. Please let me know if code is needed in any other language. I am happy to help you.Please follow the indentation as shown in the screenshot.

Added the code in java also

Code in java :

import java.io.*;

public class Main
{
   public static void main(String[] args) throws IOException{
      
      
       BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      
       System.out.println("Enter the first string : "); //taking string 1 input from the user
       String str1 = br.readLine();
       System.out.println("Enter the first string : "); //taking string 2 input from the user
       String str2 = br.readLine();
  
String p="";
      
       Main obj = new Main();
       String k = obj.recursive_same_letters(str1,str2,0,p); //calling the function
System.out.println("The string that consists of all the letters that appear in both string1 and string2 is : "+k); //printing the result
      
      
      
   }
  
   String recursive_same_letters(String s1,String s2,int i, String p)
   {
     
   if(i<s1.length()) //if i is less than the length of the string 1 then it continue to check for the characters
{ if(s2.indexOf(s1.charAt(i) )>= 0 ) // if ith character of s1 in s2 then adding it into a string
{
p=p+s1.charAt(i);
}
i=i+1; //increasing the index
return recursive_same_letters(s1,s2,i,p); //calling the function recursively
}
else //condition if checking of all characters done
{
return p; //returning the string that consists of all the characters that appear in both s1tring and string2
}
  
   }
}

Sample output:

input Enter the first string : fourth Enter the first string : faster The string that consists of all the letters that appear in both string1 and string2 is : frt

Code screenshot :

2 #recursive function find the string that consists of all the letters that appear in both string1 and string2 3- def recursive_same_letters(s1, s2,i,p): if(i<len(81)): #if i is less than the length of the string 1 then it continue to check for the characters if(s1[i] in s2): # if ith character of s1 in s2 then adding it into a string p=p+s1[i] i=i+1 #increasing the index 8 return recursive_same_letters(s1, s2,i,p) #calling the function recursively 9 else: #condition if checking of all characters done return p #returning the string that consists of all the characters that appear in both sltring and string2 10 11 22 13 str1=input("Enter the first string : ") #taking string 1 input from the user 14 str2=input("Enter the second string : ")#taking string 2 input from the user 15 p="" 16 k=recursive_same_letters(str1, str2,0,p) #calling the function 17 print("The string that consists of all the letters that appear in both string1 and string2 is : ",k) #printing the result

Sample output1:

Input Enter the first string : fourth Enter the second string : first, The string that consists of all the letters that appear in both stringi and string2 is : frt

Sample output2:

nipul Enter the first string : rizwan Enter the second string : rayyan The string that consists of all the letters that appear in both stringl and string2 is : ran

Copyable code:

#recursive function find the string that consists of all the letters that appear in both string1 and string2
def recursive_same_letters(s1,s2,i,p):
if(i<len(s1)): #if i is less than the length of the string 1 then it continue to check for the characters
if(s1[i] in s2): # if ith character of s1 in s2 then adding it into a string
p=p+s1[i]
i=i+1 #increasing the index
return recursive_same_letters(s1,s2,i,p) #calling the function recursively
else: #condition if checking of all characters done
return p #returning the string that consists of all the characters that appear in both s1tring and string2

str1=input("Enter the first string : ") #taking string 1 input from the user
str2=input("Enter the second string : ")#taking string 2 input from the user
p=""
k=recursive_same_letters(str1,str2,0,p) #calling the function
print("The string that consists of all the letters that appear in both string1 and string2 is : ",k) #printing the result