Given two string arrays words1 and words2, return the number of strings that appear exactly once in each of the two arrays.
Example 1:
Input: words1 = ["leetcode","is","amazing","as","is"], words2 = ["amazing","leetcode","is"] Output: 2 Explanation: - "leetcode" appears exactly once in each of the two arrays. We count this string. - "amazing" appears exactly once in each of the two arrays. We count this string. - "is" appears in each of the two arrays, but there are 2 occurrences of it in words1. We do not count this string. - "as" appears once in words1, but does not appear in words2. We do not count this string. Thus, there are 2 strings that appear exactly once in each of the two arrays.
Example 2:
Input: words1 = ["b","bb","bbb"], words2 = ["a","aa","aaa"] Output: 0 Explanation: There are no strings that appear in each of the two arrays.
Example 3:
Input: words1 = ["a","ab"], words2 = ["a","a","a","ab"] Output: 1 Explanation: The only string that appears exactly once in each of the two arrays is "ab".
Constraints:
1 <= words1.length, words2.length <= 10001 <= words1[i].length, words2[j].length <= 30words1[i] and words2[j] consists only of lowercase English letters.struct Solution;
use std::collections::HashMap;
impl Solution {
fn count_words(words1: Vec<String>, words2: Vec<String>) -> i32 {
let mut hm1: HashMap<String, usize> = HashMap::new();
let mut hm2: HashMap<String, usize> = HashMap::new();
for w in words1 {
*hm1.entry(w).or_default() += 1;
}
for w in words2 {
*hm2.entry(w).or_default() += 1;
}
let mut res = 0;
for (k, v) in hm1 {
if v == 1 && *hm2.get(&k).unwrap_or(&0) == 1 {
res += 1;
}
}
res
}
}
#[test]
fn test() {
let words1 = vec_string!["leetcode", "is", "amazing", "as", "is"];
let words2 = vec_string!["amazing", "leetcode", "is"];
let res = 2;
assert_eq!(Solution::count_words(words1, words2), res);
let words1 = vec_string!["b", "bb", "bbb"];
let words2 = vec_string!["a", "aa", "aaa"];
let res = 0;
assert_eq!(Solution::count_words(words1, words2), res);
let words1 = vec_string!["a", "ab"];
let words2 = vec_string!["a", "a", "a", "ab"];
let res = 1;
assert_eq!(Solution::count_words(words1, words2), res);
}