Rust, HashMap counter, split(' '), O(n)
\nuse std::collections::HashMap;\nimpl Solution {\n    pub fn largest_word_count(messages: Vec<String>, senders: Vec<String>) -> String {\n        let n = sende
```\nuse std::collections::HashMap;\nimpl Solution {\n    pub fn largest_word_count(messages: Vec<String>, senders: Vec<String>) -> String {\n        let n = senders.len();\n        let mut xs = HashMap::new();\n        let mut hi = 0;\n        let mut ans = String::new();\n        for (i, x) in senders.into_iter().enumerate() {\n            let cnt = messages[i].split(" ").collect::<Vec<&str>>().len();\n            *xs.entry(x.clone()).or_insert(0) += cnt;\n            if xs[&x] > hi || (xs[&x] == hi && x > ans) {\n                hi = xs[&x];\n                ans = x;\n            }\n        }\n        ans\n    }\n}\n```
['Rust']