Swift String Exercises: Create a new string taking the middle two characters of a given string of even length

Last update on December 21 2024 10:30:19 (UTC/GMT +8 hours)

Write a Swift program to create a new string taking the middle two characters of a given string of even length. The given string length must be at least 2.

Pictorial Presentation:

Flowchart: Swift String Exercises - Create a new string taking the middle two characters of a given string of even length.

Sample Solution:

Swift Code:

import Foundation
func middleTwo(_ str: String) -> String {
    var end_index = str.endIndex
    var start_index = str.startIndex
    
    while end_index != start_index {
        start_index = str.index(after: start_index)
        end_index = str.index(before: end_index)
    }
    
    end_index = str.index(after: end_index)
    start_index = str.index(before: start_index)
    
    return str.substring(with: Range(uncheckedBounds: (start_index, end_index)))
}
print(middleTwo("Python"))
print(middleTwo("Java"))

Sample Output:


th
av

Swift Programming Code Editor:

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