Find all possible subsequences or substring of given string

Author: Antesh Sharma

src/main/java/com/antesh/dsa/dp/CoinChangeWithMinimumCoinsProblemDP.java

@@ -36,7 +36,7 @@ else if (coins[i-1] > j) {
             }
         }
 
-        //minimum coins required will be at the mast row and column
+        //minimum coins required will be at the last row and column
         return memo[coins.length][amount];
     }
 }

src/main/java/com/antesh/dsa/string/AllPossibleSequencesOrSubString.java

@@ -0,0 +1,43 @@
+package com.antesh.dsa.string;
+/*  Find all possible substring of given input string
+*   Sample 1: AB
+*   Output 1: {}, {A}, {B}, {AB}  // i.e. 2^n possible
+*
+*   Sample 2: ABC
+*   Output 2: {}, {A}, {B}, {C}, {AB}, {AC}, {BC}, {ABC}
+* */
+
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+public class AllPossibleSequencesOrSubString {
+
+    public static void subSequence(String input, Set<String> outputs) {
+        if (input == null || input.trim().length() == 0) {
+            outputs.add("");
+            return;
+        }
+
+        subSequence(input.substring(1), outputs);
+
+        List<String> cp = outputs.stream().collect(Collectors.toList());
+        for (String s : cp) {
+            outputs.add(input.substring(0, 1) + s);
+        }
+    }
+
+    public static void main(String[] args) {
+        Set<String> outputs = new HashSet<>();
+        subSequence("ABCD",outputs);
+        System.out.println(outputs);
+        System.out.println(outputs.size());
+
+        outputs = new HashSet<>();
+        subSequence("AAAA",outputs);
+        System.out.println(outputs);
+        System.out.println(outputs.size());
+    }
+}

src/main/java/com/antesh/problems/SumOfDigits.java

@@ -6,6 +6,7 @@ public static void main(String[] args) {
         int number = 1234;
         System.out.println("sum of digits of " + number + " is " + sumOfDigits(number));
         System.out.println("sum of digits of " + number + " is " + sumInOofOneTime(number));
+        System.out.println("sum of digits of " + number + " is " + sumInOofOneTime(88));
     }
 
     //O(n)