Find subarrays with equal sum

Array Hash Table

66.9% acceptance

Feb 25, 2026

612

Given a 0-indexed integer array nums, determine whether there exist two subarrays of length 2 with equal sum. Note that the two subarrays must begin at different indices. Return true if these subarrays exist, and false otherwise. A subarray is a contiguous non-empty sequence of elements within an array.

Solution

Rust

Time O(n)

Space O(n)

LeetCode

solution.rs

impl Solution {
  pub fn find_subarrays(nums: Vec<i32>) -> bool {
    use std::collections::HashSet;
    let mut seen = HashSet::new();
    for i in 0..nums.len() - 1 {
      let s = nums[i] + nums[i + 1];
      if !seen.insert(s) { return true; }
    }
    false
  }
}