Check if a number is majority element in a sorted array

Array Binary Search

59.9% acceptance

Mar 31, 2026

480

Given an integer array nums sorted in non-decreasing order and an integer target, return true if target is a majority element, or false otherwise. A majority element in an array nums is an element that appears more than nums.length / 2 times in the array.

Solution

Rust

Time O(log n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn is_majority_element(nums: Vec<i32>, target: i32) -> bool {
    // Binary search for first and last occurrence
    let first = nums.partition_point(|&x| x < target);
    let last = nums.partition_point(|&x| x <= target);
    last - first > nums.len() / 2
  }
}