LeetCode/rb/binary-search.rb

# @param {Integer[]} nums
# @param {Integer} target
# @return {Integer}
def search(nums, target)
    left = 0
    right = nums.size

    while left < right do
        mid = (left + right).div(2)

        if nums[mid] == target then
            return mid
        elsif nums[mid] < target then
            left = mid + 1
        else
            right = mid
        end
    end

    return -1
end

RSpec.describe "search" do
    it "nums = [-1,0,3,5,9,12], target = 9" do
        expect(search([-1,0,3,5,9,12], 9)).to eq(4)
    end

    it "nums = [-1,0,3,5,9,12], target = 2" do
        expect(search([-1,0,3,5,9,12], 2)).to eq(-1)
    end
end