Add print all sequence of a string program (#30)

strings/README.md

@@ -3,6 +3,7 @@
 ### C or C++
 
 1. [Palindrome Check](c-or-cpp/palindrome.c)
+2. [All subsequences](c-or-cpp/sequence.cpp)
 
 ### C#
 You could use any online IDE (for an example [.net Finddle](https://dotnetfiddle.net/)) to test them.
@@ -16,3 +17,4 @@ You could use any online IDE (for an example [.net Finddle](https://dotnetfiddle
 ### Java
 
 1. [Palindrome Check](java/palindrome.java)
+2. [All subsequences](java/sequence.java)

strings/c-or-cpp/sequence.cpp

@@ -0,0 +1,22 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+//pick and don't pick algorithm
+//recrsion to print all subsequence
+
+void permute(string t, int i, int n, string s){
+   if(i==n)
+    {
+     cout<<t<<endl;
+    }
+   else{
+     permute(t,i+1,n,s);
+     t = t + s[i];
+     permute(t,i+1,n,s);
+       }
+ }
+   int main(){
+     string s = "abc";
+     permute("", 0 , s.length() , s );
+     return 0;
+  }

strings/java/sequence.java

@@ -0,0 +1,28 @@
+import java.util.*;
+class sequence {
+ 
+    
+    static List<String> al = new ArrayList<>();
+   
+    
+    public static void main(String[] args)
+    {
+        String s = "abc";
+        findsubsequences(s, ""); 
+        System.out.println(al);
+    }
+ 
+    private static void findsubsequences(String s,
+                                         String ans)
+    {
+        if (s.length() == 0) {
+            al.add(ans);
+            return;
+        }
+ 
+       
+        findsubsequences(s.substring(1), ans + s.charAt(0));
+ 
+        findsubsequences(s.substring(1), ans);
+    }
+}