diff --git a/Basic_Of_Algorithm/src/programmers_level_01/crain.java b/Basic_Of_Algorithm/src/programmers_level_01/crain.java
new file mode 100644
index 0000000..f43b4c5
--- /dev/null
+++ b/Basic_Of_Algorithm/src/programmers_level_01/crain.java
@@ -0,0 +1,56 @@
+package programmers_level_01;
+
+import java.util.Stack;
+
+public class crain {
+	
+	public static void main(String[] args) {
+		
+		int[][] board = {{0,0,0,0,0},{0,0,1,0,3},{0,2,5,0,1},{4,2,4,4,2},{3,5,1,3,1}};
+		int [] moves = {1,5,3,5,1,2,1,4};
+		
+		int answer = 0;
+		
+		Stack<Integer> stack = new Stack<>();
+		
+		
+		for(int mov : moves) {
+			
+			mov--;
+			
+			for(int i=0;i<board.length;i++) {
+				
+				if(board[i][mov]!=0) {
+					if(stack.isEmpty()) {
+						stack.add(board[i][mov]);
+						board[i][mov] = 0;
+						break;
+					}
+					else {
+						if(stack.peek()==board[i][mov]) {
+							stack.pop();
+							answer++;
+						}else {
+							stack.add(board[i][mov]);
+						}
+						board[i][mov] = 0;
+						break;
+					}
+					
+				}
+				
+			}
+			
+			
+		}
+		
+		
+		
+		System.out.println(answer*2);
+		
+		
+		
+		
+	}
+
+}
diff --git a/Basic_Of_Algorithm/src/programmers_level_2/change.java b/Basic_Of_Algorithm/src/programmers_level_2/change.java
new file mode 100644
index 0000000..8c146d9
--- /dev/null
+++ b/Basic_Of_Algorithm/src/programmers_level_2/change.java
@@ -0,0 +1,38 @@
+package programmers_level_2;
+
+import java.util.*;
+
+public class change {
+
+	public static void main(String[] args) {
+		
+	String [][] clothes = {{"yellowhat", "headgear"}, {"bluesunglasses", "eyewear"}, {"green_turban", "headgear"}};	
+	int answer = 1;
+	
+	HashMap<String,ArrayList<String>> map = new HashMap<>();
+	
+	for(int i=0;i<clothes.length;i++) {
+		
+		String first = clothes[i][0];
+		String second = clothes[i][1];
+		
+		if(!map.containsKey(second)) map.put(second, new ArrayList<>());
+		
+		map.get(second).add(first);
+		
+	}
+	
+	
+	
+	for(String key : map.keySet()) {
+		
+		answer *= map.get(key).size()+1;
+	}
+	
+	
+	
+	System.out.println(answer-1);
+	
+	
+	}
+}