CodeTest/leetcode/contains-duplicate/solution_1406177089.rs

use std::collections::HashSet;

impl Solution {
    pub fn contains_duplicate(nums: Vec<i32>) -> bool {
        let mut already_visit = HashSet::new();
        for num in nums{
            if already_visit.contains(&num){
                return true;
            }
            already_visit.insert(num);
        }

        return false;
    }
}