diff --git a/spring24/week4/.gitignore b/spring24/week4/.gitignore
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+/Challenge.class
diff --git a/spring24/week4/Challenge.java b/spring24/week4/Challenge.java
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+package spring24.week4;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.util.ArrayList;
+import java.util.Scanner;
+
+public class Challenge {
+
+	
+	/**
+	 * CHALLENGE 1:
+	 * Read and store the contents of a file into a String array for further processing.
+	 * 
+	 * @param f
+	 * @return
+	 */
+	public static String[] readFile(File f) {
+		if(f == null) return null; // Catch if the File does not exist.
+		
+		// TODO: Create a variable, potentially an object, to store Strings that are read in from the file.
+		
+		try (Scanner s = new Scanner(f)){
+			// TODO: Populate the variable from above with Strings from the file.
+		} catch (FileNotFoundException e) {
+			e.printStackTrace();
+		}
+		
+		return null; // TODO: Return the variable.
+	}
+	
+	/**
+	 * CHALLENGE 2:
+	 * Given an input String array, store each token in an ArrayList.
+	 * 
+	 * A token is a single word, symbol, or character, surrounded on both sides by a space.
+	 * 
+	 * @param s
+	 * @return
+	 */
+	public static ArrayList<String> split(String[] s) {
+		ArrayList<String> list = new ArrayList<String>();
+		
+		// TODO: Take the input String array s and add each separate word (separated by a space) to the ArrayList.
+		
+		return list;
+	}
+	
+	/**
+	 * CHALLENGE 3:
+	 * Given an input ArrayList of tokens (assume all are valid integers, doubles, or operations ('+','-','*','/','%','(', and ')')),
+	 * calculate the result using correct order of operations.
+	 * 
+	 * HINT: Think of a data structure that might be useful for this.
+	 * 
+	 * @param tokens
+	 */
+	public static double calculate(ArrayList<String> tokens) {
+		return 0.0; // TODO: Implement this method.
+	}
+	
+	public static boolean testChallenge1(String[] s) {
+		return false; // TODO
+	}
+	
+	public static boolean testChallenge2(ArrayList<String> list) {
+		return false; // TODO
+	}
+	
+	public static boolean testChallenge3(double result) {
+		return false; // TODO
+	}
+	
+	public static void main(String[] args) {
+		
+	}
+}
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