1897. Redistribute Characters to Make All Strings Equal: AC

Author: tan-wei

src/solution/mod.rs

@@ -1429,3 +1429,4 @@ mod s1893_check_if_all_the_integers_in_a_range_are_covered;
 mod s1894_find_the_student_that_will_replace_the_chalk;
 mod s1895_largest_magic_square;
 mod s1896_minimum_cost_to_change_the_final_value_of_expression;
+mod s1897_redistribute_characters_to_make_all_strings_equal;

src/solution/s1897_redistribute_characters_to_make_all_strings_equal.rs

@@ -0,0 +1,80 @@
+/**
+ * [1897] Redistribute Characters to Make All Strings Equal
+ *
+ * You are given an array of strings words (0-indexed).
+ * In one operation, pick two distinct indices i and j, where words[i] is a non-empty string, and move any character from words[i] to any position in words[j].
+ * Return true if you can make every string in words equal using any number of operations, and false otherwise.
+ *  
+ * Example 1:
+ *
+ * Input: words = ["abc","aabc","bc"]
+ * Output: true
+ * Explanation: Move the first 'a' in words[1] to the front of words[2],
+ * to make words[1] = "abc" and words[2] = "abc".
+ * All the strings are now equal to "abc", so return true.
+ *
+ * Example 2:
+ *
+ * Input: words = ["ab","a"]
+ * Output: false
+ * Explanation: It is impossible to make all the strings equal using the operation.
+ *
+ *  
+ * Constraints:
+ *
+ * 	1 <= words.length <= 100
+ * 	1 <= words[i].length <= 100
+ * 	words[i] consists of lowercase English letters.
+ *
+ */
+pub struct Solution {}
+
+// problem: https://leetcode.com/problems/redistribute-characters-to-make-all-strings-equal/
+// discuss: https://leetcode.com/problems/redistribute-characters-to-make-all-strings-equal/discuss/?currentPage=1&orderBy=most_votes&query=
+
+// submission codes start here
+
+impl Solution {
+    pub fn make_equal(words: Vec<String>) -> bool {
+        let mut hm = std::collections::HashMap::new();
+
+        for word in &words {
+            for c in word.chars() {
+                *hm.entry(c).or_insert(0) += 1;
+            }
+        }
+
+        for letter in hm.values() {
+            if *letter % words.len() != 0 {
+                return false;
+            }
+        }
+
+        true
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_1897_example_1() {
+        let words = vec_string!["abc", "aabc", "bc"];
+
+        let result = true;
+
+        assert_eq!(Solution::make_equal(words), result);
+    }
+
+    #[test]
+    fn test_1897_example_2() {
+        let words = vec_string!["ab", "a"];
+
+        let result = false;
+
+        assert_eq!(Solution::make_equal(words), result);
+    }
+}