diff --git a/README.md b/README.md
index da57339..ea1f596 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,6 @@
-This repository contains answers to the assignments of Advent of Coding 2022
+# Advent of Code 2022 - Assignment7 javascript
+Assignment 7 involves parsing linux directory commands/results into a tree. The solution defines a root TreeNode first and sets it as currentdirectory. Whenever a cd command is found a new node is created if it does not exist and set to currentdir. Whenever a cd .. is found currentdirectory is set to parent. Whenever a file is found size is recursively increased for current node and parent nodes.
+
+## References
+- https://adrianmejia.com/data-structures-for-beginners-trees-binary-search-tree-tutorial/
+- https://stackoverflow.com/questions/8376525/get-value-of-a-string-after-last-slash-in-javascript
diff --git a/script.js b/script.js
index a6e2848..ac54366 100644
--- a/script.js
+++ b/script.js
@@ -1,6 +1,9 @@
 const ASSIGNMENT = 'assignment';
 const ANSWER = 'answer';
 const NEWLINE_CHARACTER = '\n';
+const MAX_SIZE = 100000;
+const UPDATE_SIZE = 30000000;
+const TOTAL_SPACE = 70000000;
 
 /**
  * Main function
@@ -9,6 +12,76 @@ window.onload = function() {
     document.getElementById(ASSIGNMENT).addEventListener("input", calculateAnswer);
 }
 
+class TreeNode {
+  constructor(value, parent) {
+    console.debug(((!parent)?"Root ":"") + "node created: " + value);
+
+    this.parent = parent;
+    this.value = value;
+    this.size = 0;
+    this.descendants = [];
+  }
+
+  getDir = function(path) {
+    for(let descendant of this.descendants) {
+      if(descendant.value == path) {
+        return descendant;
+      }
+    }
+  }
+
+  contains = function(path) {
+    // Recursive case
+    let subPathIndex = path.indexOf('/');
+    let subPath = path.substring(0, subPathIndex-1);
+    let leftOverPath = path.substring(subPathIndex);
+
+    // Base case
+    if(subPath == '') {
+      return false;
+    }
+
+    for(let descendant of this.descendants) {
+      if(descendant.value == subPath) {
+        return descendant.contains(subPath);
+      }
+    }
+  }
+
+  findClosestNodeToSize = function(minSize) {
+    let closest = this;
+
+    for(let descendant of this.descendants) {
+      let closestDescendant = descendant.findClosestNodeToSize(minSize);
+
+      if (closestDescendant.size > minSize && closestDescendant.size < closest.size) {
+        console.debug("New closest:" + closestDescendant.size);
+        closest = closestDescendant;
+      }
+    }
+
+    return closest;
+  }
+
+  increaseSize = function(size) {
+    // TODO: Wat doen we met duplicate files?
+    this.size += size;
+    if(this.parent) {
+      this.parent.increaseSize(size);
+    }
+  }
+
+  getSum = function(maxSize) {
+    let result = (this.size < maxSize) ? this.size: 0;
+
+    for(let descendant of this.descendants) {
+      result += descendant.getSum(maxSize);
+    }
+
+    return result;
+  }
+}
+
 /**
  * Listener function for input in assignment field.
  * @param event the onInput event 
@@ -26,8 +99,49 @@ function calculateAnswer(event) {
  * @return string the answer
  */
 function algorithm(assignment) {
-    let lines = assignment.trim().split(NEWLINE_CHARACTER);
-    console.info("Linecount:" + lines.length);
+  let lines = assignment.trim().split(NEWLINE_CHARACTER);
+  console.info("Linecount:" + lines.length);
 
-    // TODO: implement assignment
+  let root = new TreeNode('/');
+  let currentdir = root;
+
+  for(let i=0; i<lines.length; i++) {
+    let terminalLine = lines[i].trim();
+
+    if(terminalLine.substring(0, 4) == "$ cd") {
+      let changeDirectory = terminalLine.substring(5).trim();
+      if(changeDirectory == "..") {
+        console.debug("One directory up from: " + currentdir.value);
+        currentdir = currentdir.parent;
+        console.debug("navigates to: " + currentdir.value);
+        continue;
+      }
+
+      if(changeDirectory == "/") {
+        currentdir = root;
+        continue;
+      }
+
+      if(!currentdir.contains(changeDirectory)) {
+        currentdir.descendants.push(new TreeNode(changeDirectory, currentdir));
+      } 
+
+      currentdir = currentdir.getDir(changeDirectory);
+    } else if(terminalLine.substring(0, 3) != 'dir' && !terminalLine.includes('$')) {
+      console.debug(terminalLine);
+      spaceIndex = terminalLine.indexOf(' ');
+      size = parseInt(terminalLine.substring(0, spaceIndex));
+      currentdir.increaseSize(size);
+    }
+  }
+
+  let freeDiskSpace = TOTAL_SPACE - root.size;
+  console.debug("Free disk space: " + freeDiskSpace);
+
+  console.debug("Root size:" + root.size);
+  console.debug("Value to find: " + (UPDATE_SIZE - freeDiskSpace));
+  let closestNode = root.findClosestNodeToSize(UPDATE_SIZE - freeDiskSpace);
+  console.debug("Closest value: " + closestNode.size);
+
+  return "Sum below maxSize " + MAX_SIZE + ": " + root.getSum(MAX_SIZE);
 }
\ No newline at end of file