This article will deal with the problem of finding the K-th number in an array. This problem is one of the types that frequently appears in coding tests and requires an understanding of array sorting and indexing. Let’s learn how to utilize Kotlin’s useful features and implement optimized algorithms in the process of solving this problem.<\/p>\n
Given an integer array After sorting the array in ascending order, output the K-th number.<\/p>\n To solve the problem, the following steps must be taken:<\/p>\n Kotlin is a modern language that supports both functional programming and object-oriented programming simultaneously. Therefore, it allows writing very concise and intuitive code when solving this problem.<\/p>\n The above code consists of the following parts:<\/p>\n The time complexity of this problem is proportional to the time required to sort the array. The sorting algorithm typically requires O(N log N) time, and the process of finding the K-th number takes O(1). Therefore, the overall time complexity is O(N log N).<\/p>\n In this article, we discussed the problem of finding the K-th number in an array and examined a simple implementation method using Kotlin. Since problems like this will frequently appear in future coding test preparations, it is important to enhance understanding of algorithms and improve coding skills through repetitive practice.<\/p>\n Additionally, when solving algorithm problems, one should pay attention to the following points:<\/p>\narr<\/code> and an integer K<\/code>, write a function that returns the K-th number after sorting the array in ascending order. The array indices start from 0, and K is between 1 and the size of the array.<\/p>\nInput<\/h3>\n
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Output<\/h3>\n
Example<\/h3>\n
\nInput\n5\n3 1 2 5 4\n2\n\nOutput\n2\n<\/pre>\n
Problem Analysis<\/h2>\n
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Implementing in Kotlin<\/h2>\n
Code Implementation<\/h3>\n
\nfun findKthNumber(arr: IntArray, k: Int): Int {\n \/\/ Sort the array in ascending order\n val sortedArray = arr.sortedArray()\n \/\/ Return the K-th number (k-1 index)\n return sortedArray[k - 1]\n}\n\nfun main() {\n \/\/ Set initial values\n val n = 5\n val inputArray = intArrayOf(3, 1, 2, 5, 4)\n val k = 2\n\n \/\/ Find the K-th number\n val result = findKthNumber(inputArray, k)\n println(result)\n}\n<\/code><\/pre>\nCode Explanation<\/h2>\n
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sortedArray<\/code> method to easily sort the array.<\/li>\nfindKthNumber<\/code> function to output the result.<\/li>\n<\/ol>\nTime Complexity Analysis<\/h2>\n
Conclusion<\/h2>\n