kirkdrichardson · October 12, 2019 02:49
diff --git a/main.dart b/main.dart
  
  /**
   * 
   * Frequency Counter Pattern in Dart - anagram challenge
   * 
   * Problem Description:
   * 
   * Given two strings, write a function to determine if the second string is an anagram
   * of the first. Do not worry about whitespace or non-alphanumeric characters.
   * 
   * */

 // See live at https://dartpad.dartlang.org/b442b5989a0e1066577d30d1f6c6993f
  
 void main() {

  // Test cases
  print("Test 1: ${assertBool(false, isAnagram('aww', 'ape'))}");
  print("Test 2: ${assertBool(false, isAnagram('an', 'app'))}");
  print("Test 3: ${assertBool(true, isAnagram('apple', 'plepa'))}");
  print("Test 4: ${assertBool(true, isAnagram('race', 'crae'))}");
  print("Test 4: ${assertBool(true, isAnagram('ppppp', 'ppppp'))}");
  print("Test 5: ${assertBool(true, isAnagram('', ''))}");
 }


 // Method to return boolean if anagram
 bool isAnagram(String s1, String s2) {
  if (s1.length != s2.length) return false;
  
  Map<String, int> charCount = Map();
  
  // One iteration through first array, O(n).
  for (String char in s1.split('')) {
    // Update the map by incrementing or adding cnt value for character.
    charCount.update(char, (cnt) => ++cnt, ifAbsent: () => 1);
  }

  // One iteration through second array, O(n).
  for (String c in s2.split('')) {
    // Make sure key exists. If not, early return.
    if (!charCount.containsKey(c)) return false;
    // Decrement the count and get the updated value.
    int updatedCount = charCount.update(c, (cnt) => --cnt);
    // If the count is negative, the second word had more instances of char.
    if (updatedCount < 0) return false;
  }
  
  // Only an anagram could make it this far 🎼🎼🎼🎼
  return true;
 }

 String assertBool(bool b1, bool b2) => b1 == b2 ? 'PASS' : 'FAIL';

	/**
	*
	* Frequency Counter Pattern in Dart - anagram challenge
	*
	* Problem Description:
	*
	* Given two strings, write a function to determine if the second string is an anagram
	* of the first. Do not worry about whitespace or non-alphanumeric characters.
	*
	* */

	// See live at https://dartpad.dartlang.org/b442b5989a0e1066577d30d1f6c6993f

	void main() {

	// Test cases
	print("Test 1: ${assertBool(false, isAnagram('aww', 'ape'))}");
	print("Test 2: ${assertBool(false, isAnagram('an', 'app'))}");
	print("Test 3: ${assertBool(true, isAnagram('apple', 'plepa'))}");
	print("Test 4: ${assertBool(true, isAnagram('race', 'crae'))}");
	print("Test 4: ${assertBool(true, isAnagram('ppppp', 'ppppp'))}");
	print("Test 5: ${assertBool(true, isAnagram('', ''))}");
	}


	// Method to return boolean if anagram
	bool isAnagram(String s1, String s2) {
	if (s1.length != s2.length) return false;

	Map<String, int> charCount = Map();

	// One iteration through first array, O(n).
	for (String char in s1.split('')) {
	// Update the map by incrementing or adding cnt value for character.
	charCount.update(char, (cnt) => ++cnt, ifAbsent: () => 1);
	}

	// One iteration through second array, O(n).
	for (String c in s2.split('')) {
	// Make sure key exists. If not, early return.
	if (!charCount.containsKey(c)) return false;
	// Decrement the count and get the updated value.
	int updatedCount = charCount.update(c, (cnt) => --cnt);
	// If the count is negative, the second word had more instances of char.
	if (updatedCount < 0) return false;
	}

	// Only an anagram could make it this far 🎼🎼🎼🎼
	return true;
	}

	String assertBool(bool b1, bool b2) => b1 == b2 ? 'PASS' : 'FAIL';