Distant barcodes

Array Hash Table Greedy Sorting Heap (Priority Queue) Counting

48.6% acceptance

Feb 25, 2026

1347

In a warehouse, there is a row of barcodes, where the ith barcode is barcodes[i]. Rearrange the barcodes so that no two adjacent barcodes are equal. You may return any answer, and it is guaranteed an answer exists.

Solution

Rust

Time O(n²)

Space O(n)

LeetCode

solution.rs

impl Solution {
  pub fn rearrange_barcodes(barcodes: Vec<i32>) -> Vec<i32> {
    let n = barcodes.len();
    let mut freq: std::collections::HashMap<i32, usize> = std::collections::HashMap::new();
    for &b in &barcodes { *freq.entry(b).or_insert(0) += 1; }
    let mut sorted: Vec<(usize, i32)> = freq.into_iter().map(|(k,v)| (v,k)).collect();
    sorted.sort_unstable_by(|a,b| b.cmp(a));
    let mut res = vec![0i32; n];
    let mut idx = 0usize;
    for (cnt, val) in sorted {
      for _ in 0..cnt {
        if idx >= n { idx = 1; }
        res[idx] = val;
        idx += 2;
      }
    }
    res
  }
}