1160. Find Words That Can Be Formed by Characters (#173)

Author: remy727

README.md

@@ -317,6 +317,7 @@
 | 1143 | Longest Common Subsequence | [Ruby](./algorithms/ruby/1143-longest-common-subsequence.rb) | Medium |
 | 1146 | Snapshot Array | [Ruby](./algorithms/ruby/1146-snapshot-array.rb) | Medium |
 | 1155 | Number of Dice Rolls With Target Sum | [Ruby](./algorithms/ruby/1155-number-of-dice-rolls-with-target-sum.rb) | Medium |
+| 1160 | Find Words That Can Be Formed by Characters | [Ruby](./algorithms/ruby/1160-find-words-that-can-be-formed-by-characters.rb) | Easy |
 | 1161 | Maximum Level Sum of a Binary Tree | [Ruby](./algorithms/ruby/1161-maximum-level-sum-of-a-binary-tree.rb) | Medium |
 | 1162 | As Far from Land as Possible | [Ruby](./algorithms/ruby/1162-as-far-from-land-as-possible.rb) | Medium |
 | 1187 | Make Array Strictly Increasing | [Ruby](./algorithms/ruby/1187-make-array-strictly-increasing.rb) | Hard |

algorithms/ruby/1160-find-words-that-can-be-formed-by-characters.rb

@@ -0,0 +1,70 @@
+# frozen_string_literal: true
+
+# 1160. Find Words That Can Be Formed by Characters
+# Easy
+# https://leetcode.com/problems/find-words-that-can-be-formed-by-characters
+
+=begin
+You are given an array of strings words and a string chars.
+A string is good if it can be formed by characters from chars (each character can only be used once).
+Return the sum of lengths of all good strings in words.
+
+Example 1:
+Input: words = ["cat","bt","hat","tree"], chars = "atach"
+Output: 6
+Explanation: The strings that can be formed are "cat" and "hat" so the answer is 3 + 3 = 6.
+
+Example 2:
+Input: words = ["hello","world","leetcode"], chars = "welldonehoneyr"
+Output: 10
+Explanation: The strings that can be formed are "hello" and "world" so the answer is 5 + 5 = 10.
+
+Constraints:
+1 <= words.length <= 1000
+1 <= words[i].length, chars.length <= 100
+words[i] and chars consist of lowercase English letters.
+=end
+
+# @param {String[]} words
+# @param {String} chars
+# @return {Integer}
+def count_characters(words, chars)
+  char_hash = {}
+  chars.each_char do |char|
+    char_hash[char] ||= 0
+    char_hash[char] += 1
+  end
+
+  answer = 0
+  words.each do |word|
+    char_hash_clone = char_hash.clone
+
+    has_all = true
+    word.each_char do |c|
+      if char_hash_clone[c] && (char_hash_clone[c] > 0)
+        char_hash_clone[c] -= 1
+      else
+        has_all = false
+        break
+      end
+    end
+
+    if has_all
+      answer += word.size
+    end
+  end
+
+  answer
+end
+
+# **************** #
+#       TEST       #
+# **************** #
+
+require "test/unit"
+class Test_count_characters < Test::Unit::TestCase
+  def test_
+    assert_equal 6, count_characters(["cat","bt","hat","tree"], "atach")
+    assert_equal 10, count_characters(["hello","world","leetcode"], "welldonehoneyr")
+  end
+end