use std::collections::HashMap; struct Solution; impl Solution { pub fn contains_nearby_duplicate(nums: Vec, k: i32) -> bool { let mut hm = HashMap::new(); for (i, n) in nums.iter().enumerate() { if let Some(j) = hm.insert(n, i) { if (i as i32) - (j as i32) <= k { return true; } } } false } } fn main() { let nums = vec![1,2,3,1]; print!("{}", Solution::contains_nearby_duplicate(nums, 3)); }