I thought that I could deepen my understanding by verbalizing things that seem a little complicated. I would appreciate it if you could point out better expressions and mistakes.

--What is binary search? --Search process

--Practice --Problem --Answer

--Summary

--References

This technique is used to search for data in sorted lists and arrays. We will search by narrowing down the target data to half.

-** Use ** while ** to search repeatedly until the value ** and ** the data you want to search match **

--Is the data you want to search ** to the right of half? Is it on the left? ** ** -Or ** Doesn't it exist in the array? ** **

Find out if any value exists in the array and what number it exists.

```
def binary_search(ary, target)
left = 0 #Array starts at 0th
right = ary.length - 1 #The end of the array (th)
while left <= right #Until you find the value you want
center = (left + right) / 2 #Get the middle of the array
if ary[center] == target #Once you have the array subscript and the number you want to search for
return "#{target}Is an array#{center + 1}Exists second" #Return the result with return
elsif ary[center] < target #If the number you want to search is more than half to the right
left = center + 1 #Add 1 to the subscript to search on the right side of the half
else #If the number you want to search is more than half to the left
right = center - 1 #Subtract 1 from the subscript to search to the left of the half
end
end
return "#{target}Does not exist in the array" #When the while condition is not met and the search is not found
end
#Array
ary = [1, 3, 5, 6, 9, 14, 24, 33, 45, 53]
#Enter the number you want to search in the terminal
p 'Please enter the number you want to search'
#Because it is a number, to_use i
target = gets.to_i
#Binary the sorted array and the number you want to search_Pass it to the search method.
p binary_search(ary, target)
```

--Binary search is a method used to search data in sorted lists and arrays. --Narrow down the value while dividing it into two

-I wrote a binary search method in Ruby

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