diff --git "a/\353\260\225\354\244\200\354\233\220/Marathon (solution).txt" "b/\353\260\225\354\244\200\354\233\220/etc/Marathon (solution).txt"
similarity index 100%
rename from "\353\260\225\354\244\200\354\233\220/Marathon (solution).txt"
rename to "\353\260\225\354\244\200\354\233\220/etc/Marathon (solution).txt"
diff --git "a/\353\260\225\354\244\200\354\233\220/Marathon.py" "b/\353\260\225\354\244\200\354\233\220/etc/Marathon.py"
similarity index 100%
rename from "\353\260\225\354\244\200\354\233\220/Marathon.py"
rename to "\353\260\225\354\244\200\354\233\220/etc/Marathon.py"
diff --git "a/\353\260\225\354\244\200\354\233\220/etc/TargetNumber solution.txt" "b/\353\260\225\354\244\200\354\233\220/etc/TargetNumber solution.txt"
new file mode 100644
index 0000000..b0dc319
--- /dev/null
+++ "b/\353\260\225\354\244\200\354\233\220/etc/TargetNumber solution.txt"	
@@ -0,0 +1,36 @@
+타겟 넘버
+
+[input]
+numbers
+target
+
+[output]
+방법의 개수
+
+--------------------------------------------------------
+
+더하고 빼기 두가지 경우
+
+{a, b, c, d}
+
+struct node { 
+node left
+node right
+int value
+}
+
+
+   0
+2 a -a				
+4 b -b b -b
+8 c -c c -c c -c c -c
+16 d -d d -d d -d d -d d -d
+
+
+1 + 2 + 4 + 8 + 16
+==> maketree
+
+==> find target
+root부터 leaf까지 가는 모든 경우의 수를 탐색함
+모든 경우의 수의 sum을 구함
+target과 같으면 count
\ No newline at end of file
diff --git "a/\353\260\225\354\244\200\354\233\220/etc/TargetNumber.py" "b/\353\260\225\354\244\200\354\233\220/etc/TargetNumber.py"
new file mode 100644
index 0000000..e8abe42
--- /dev/null
+++ "b/\353\260\225\354\244\200\354\233\220/etc/TargetNumber.py"
@@ -0,0 +1,35 @@
+class Node:
+    def __init__(self, num):
+        self.value = num
+        self.left = None
+        self.right = None
+
+def buildTree(node, num):
+    if node.left == None and node.right == None:
+        node.left = Node(num)
+        node.right = Node(-num)
+        return
+
+    buildTree(node.left, num)
+    buildTree(node.right, num)
+
+def count(node, sum, target):
+    if node.left == None and node.right == None:
+        temp = sum + node.value
+        if temp == target:
+            return 1
+        else:
+            return 0
+
+    return count(node.left, node.value + sum, target) + count(node.right, node.value + sum, target)
+
+
+numbers = [1, 2, 3, 4, 5]
+target = 15
+
+root = Node(0)
+
+for num in numbers:
+    buildTree(root, num)
+
+print(count(root, 0, target))
\ No newline at end of file