60 lines
1.8 KiB
Java
60 lines
1.8 KiB
Java
|
/*
|
||
|
|
This program will return all the subsequences of the input string in a string array;
|
||
|
|
Sample Input:
|
||
|
|
abc
|
||
|
|
Sample Output:
|
||
|
|
"" ( Empty String )
|
||
|
|
c
|
||
|
|
b
|
||
|
|
bc
|
||
|
|
a
|
||
|
|
ac
|
||
|
|
ab
|
||
|
|
abc
|
||
|
|
|
||
|
|
*/
|
||
|
|
|
||
|
|
import java.util.Scanner;
|
||
|
|
|
||
|
|
public class ReturnSubsequence {
|
||
|
|
/*
|
||
|
|
Main function will accept the given string and implement return subsequences function
|
||
|
|
*/
|
||
|
|
public static void main(String[] args) {
|
||
|
|
System.out.println("Enter String: ");
|
||
|
|
Scanner s=new Scanner(System.in);
|
||
|
|
String givenString=s.next(); //given string
|
||
|
|
String[] subsequence=returnSubsequence(givenString); //calling returnSubsequence() function
|
||
|
|
System.out.println("Subsequences : ");
|
||
|
|
for(int i=0;i<subsequence.length;i++) //print the given array of subsequences
|
||
|
|
{
|
||
|
|
System.out.println(subsequence[i]);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
/*
|
||
|
|
Recursive function to return Subsequences
|
||
|
|
*/
|
||
|
|
private static String[] returnSubsequence(String givenString) {
|
||
|
|
if(givenString.length()==0) // If string is empty we will create an array of size=1 and insert "" (Empty string) in it
|
||
|
|
{
|
||
|
|
String[] ans=new String[1];
|
||
|
|
ans[0]="";
|
||
|
|
return ans;
|
||
|
|
|
||
|
|
}
|
||
|
|
String[] SmallAns=returnSubsequence(givenString.substring(1)); //recursive call to get subsequences of substring starting from index position=1
|
||
|
|
|
||
|
|
String[] ans=new String[2*SmallAns.length];// Our answer will be an array off string of size=2*SmallAns
|
||
|
|
int i=0;
|
||
|
|
for (;i<SmallAns.length;i++)
|
||
|
|
{
|
||
|
|
ans[i]=SmallAns[i]; //Copying all the strings present in SmallAns to ans string array
|
||
|
|
}
|
||
|
|
for (int k=0;k<SmallAns.length;k++)
|
||
|
|
{
|
||
|
|
ans[k+SmallAns.length]=givenString.charAt(0)+SmallAns[k]; // Insert character at index=0 of the given substring in front of every string in SmallAns
|
||
|
|
}
|
||
|
|
return ans;
|
||
|
|
}
|
||
|
|
}
|