thảo luận Leetcode mỗi ngày

return [word for word, count in Counter(s1.split() + s2.split()).items() if count == 1]

class Solution {
    public String[] uncommonFromSentences(String s1, String s2) {
        HashMap<String, Integer> map = new HashMap<>();

        for(String s : s1.split(" ")) {
            if (map.get(s) == null)
                map.put(s, 1);
            
            else
                map.put(s, map.get(s) + 1);
        }

        for(String s : s2.split(" ")) {
            if (map.get(s) == null)
                map.put(s, 1);
            
            else
                map.put(s, map.get(s) + 1);
        }

        List<String> list = new ArrayList<>();
        for(Map.Entry<String, Integer> entry : map.entrySet()) {
            if (entry.getValue() < 2)
                list.add(entry.getKey());
        }

        return list.toArray(new String[list.size()]);
    }
}

use::std::collections::HashMap;
impl Solution {
    pub fn two_sum(nums: Vec<i32>, target: i32) -> Vec<i32> {
        let mut my_map = HashMap::new();
        
        for (i, num) in nums.iter().enumerate() {
            let complement = target - num;
            if let Some(j) = my_map.get(&complement) {
                return vec![*j, i as i32]
            }
            my_map.insert(num,i as i32);
        }
        vec![]
    }
    pub fn two_sum_brute_force(nums: Vec<i32>, target: i32) -> Vec<i32> {
        for i in 0..nums.len() {
            for j in i + 1 .. nums.len() {
                if nums[i] + nums[j] == target {
                    return vec![i as i32,j  as i32]
                }
            }
        }
        vec![]
    }
}

class Solution {
    /**
     * @param String $s1
     * @param String $s2
     * @return String[]
     */
    function uncommonFromSentences($s1, $s2) {
        $s = $s1." ".$s2;
        $freq = [];

        // count words in s
        $arr = explode(" ", $s);
        foreach ($arr as $words) {
            if (!isset($freq[$words])) $freq[$words] = 0;
            $freq[$words]++;
        }

        // find the uncommon words
        $ans = [];
        foreach ($freq as $word => $count) {
            if ($count > 1) continue;
            $ans[] = $word;
        }
        return $ans;
    }
}

public String[] uncommonFromSentences(String s1, String s2) {
    Map<String, Integer> counter = new HashMap<>();
    for (String s : s1.split(" ")) {
        counter.put(s, counter.getOrDefault(s, 0) + 1);
    }
    for (String s : s2.split(" ")) {
        counter.put(s, counter.getOrDefault(s, 0) + 1);
    }
    List<String> result = new ArrayList<>();
    counter.forEach((k, v) -> {
        if (v == 1) {
            result.add(k);
        }
    });
    return result.toArray(String[]::new);
}