JavaScript S\u0131ralama Algoritmalar\u0131: Kabarc\u0131k, Ekleme, Se\u00e7me ve Birle\u015ftirme<\/p>\n
Merhaba! Bu makalede, JavaScript’te s\u0131k kullan\u0131lan d\u00f6rt temel s\u0131ralama algoritmas\u0131n\u0131 ele alaca\u011f\u0131z: Kabarc\u0131k S\u0131ralama (Bubble Sort), Ekleme S\u0131ralama (Insertion Sort), Se\u00e7me S\u0131ralama (Selection Sort) ve Birle\u015ftirme S\u0131ralama (Merge Sort). Her algoritman\u0131n \u00e7al\u0131\u015fma prensibini, karma\u015f\u0131kl\u0131\u011f\u0131n\u0131 ve \u00f6rnek kodlar\u0131n\u0131 detayl\u0131 olarak inceleyece\u011fiz. Ayr\u0131ca, bu algoritmalar\u0131 kar\u015f\u0131la\u015ft\u0131rarak hangi durumlarda hangisinin daha uygun oldu\u011funu g\u00f6rece\u011fiz. Umar\u0131m faydal\u0131 bulursunuz!<\/p>\n
Kabarc\u0131k s\u0131ralama, en basit s\u0131ralama algoritmalar\u0131ndan biridir. Listeyi yineleyerek, biti\u015fik elemanlar\u0131 kar\u015f\u0131la\u015ft\u0131r\u0131r ve gerekirse yer de\u011fi\u015ftirir. Bu i\u015flem, listenin sonuna kadar tekrarlan\u0131r. B\u00fcy\u00fck elemanlar, t\u0131pk\u0131 kabarc\u0131klar gibi listenin sonuna do\u011fru “y\u00fckselir”.<\/p>\n
\nfunction bubbleSort(arr) {\n let swapped;\n do {\n swapped = false;\n for (let i = 0; i < arr.length - 1; i++) {\n if (arr[i] > arr[i + 1]) {\n [arr[i], arr[i + 1]] = [arr[i + 1], arr[i]];\n swapped = true;\n }\n }\n } while (swapped);\n return arr;\n}\n<\/code><\/pre>\nKabarc\u0131k s\u0131ralama, O(n\u00b2) zaman karma\u015f\u0131kl\u0131\u011f\u0131na sahiptir. Bu nedenle, b\u00fcy\u00fck listeler i\u00e7in olduk\u00e7a yava\u015ft\u0131r. Ancak, basitli\u011fi ve anla\u015f\u0131l\u0131rl\u0131\u011f\u0131 nedeniyle, e\u011fitim ama\u00e7l\u0131 olarak s\u0131k\u00e7a kullan\u0131l\u0131r. \u00d6rne\u011fin, k\u00fc\u00e7\u00fck bir diziyi s\u0131ralamak i\u00e7in olduk\u00e7a uygundur.<\/p>\n
Ekleme S\u0131ralama (Insertion Sort)<\/h2>\n
Ekleme s\u0131ralama, dizinin bir k\u0131sm\u0131n\u0131 s\u0131ral\u0131 tutarak \u00e7al\u0131\u015f\u0131r. S\u0131radaki eleman\u0131 al\u0131r ve s\u0131ral\u0131 k\u0131s\u0131mda do\u011fru yerine yerle\u015ftirir. Bu i\u015flem, t\u00fcm elemanlar s\u0131ral\u0131 olana kadar tekrarlan\u0131r.<\/p>\n
\nfunction insertionSort(arr) {\n for (let i = 1; i < arr.length; i++) {\n let key = arr[i];\n let j = i - 1;\n while (j >= 0 && arr[j] > key) {\n arr[j + 1] = arr[j];\n j--;\n }\n arr[j + 1] = key;\n }\n return arr;\n}\n<\/code><\/pre>\nEkleme s\u0131ralama, en k\u00f6t\u00fc durumda O(n\u00b2) zaman karma\u015f\u0131kl\u0131\u011f\u0131na, en iyi durumda ise O(n) zaman karma\u015f\u0131kl\u0131\u011f\u0131na sahiptir. Kabarc\u0131k s\u0131ralamaya g\u00f6re daha verimlidir, \u00f6zellikle k\u00fc\u00e7\u00fck veya neredeyse s\u0131ral\u0131 listeler i\u00e7in tercih edilebilir. Yani, b\u00fcy\u00fck bir veri k\u00fcmesi i\u00e7in uygun olmayabilir.<\/p>\n
Se\u00e7me S\u0131ralama (Selection Sort)<\/h2>\n
Se\u00e7me s\u0131ralama, her yinelemede en k\u00fc\u00e7\u00fck (veya en b\u00fcy\u00fck) eleman\u0131 bulup onu s\u0131ral\u0131 k\u0131sm\u0131n sonuna yerle\u015ftirir. Bu i\u015flem, t\u00fcm elemanlar s\u0131ral\u0131 olana kadar devam eder.<\/p>\n
\nfunction selectionSort(arr) {\n for (let i = 0; i < arr.length - 1; i++) {\n let minIndex = i;\n for (let j = i + 1; j < arr.length; j++) {\n if (arr[j] < arr[minIndex]) {\n minIndex = j;\n }\n }\n [arr[i], arr[minIndex]] = [arr[minIndex], arr[i]];\n }\n return arr;\n}\n<\/code><\/pre>\nSe\u00e7me s\u0131ralama da O(n\u00b2) zaman karma\u015f\u0131kl\u0131\u011f\u0131na sahiptir. Ancak, yer de\u011fi\u015ftirme i\u015flemlerinin say\u0131s\u0131 di\u011fer O(n\u00b2) algoritmalara g\u00f6re daha azd\u0131r, bu da performans a\u00e7\u0131s\u0131ndan k\u00fc\u00e7\u00fck bir avantaj sa\u011flayabilir. Yine, b\u00fcy\u00fck veri setlerinde performans problemi ya\u015fayabiliriz.<\/p>\n
Birle\u015ftirme S\u0131ralama (Merge Sort)<\/h2>\n
Birle\u015ftirme s\u0131ralama, \"b\u00f6l ve y\u00f6net\" (divide and conquer) yakla\u015f\u0131m\u0131n\u0131 kullanan bir algoritmad\u0131r. Listeyi s\u00fcrekli olarak ikiye b\u00f6ler, her alt listeyi s\u0131ralar ve sonras\u0131nda bu s\u0131ral\u0131 alt listeleri birle\u015ftirir.<\/p>\n
\nfunction mergeSort(arr) {\n if (arr.length <= 1) {\n return arr;\n }\n const mid = Math.floor(arr.length \/ 2);\n const left = arr.slice(0, mid);\n const right = arr.slice(mid);\n return merge(mergeSort(left), mergeSort(right));\n}\n\nfunction merge(left, right) {\n let result = [];\n let i = 0;\n let j = 0;\n while (i < left.length && j < right.length) {\n if (left[i] < right[j]) {\n result.push(left[i]);\n i++;\n } else {\n result.push(right[j]);\n j++;\n }\n }\n return result.concat(left.slice(i)).concat(right.slice(j));\n}\n<\/code><\/pre>\nBirle\u015ftirme s\u0131ralama, O(n log n) zaman karma\u015f\u0131kl\u0131\u011f\u0131na sahiptir. Bu, di\u011fer algoritmalara g\u00f6re \u00e7ok daha verimlidir ve b\u00fcy\u00fck listeler i\u00e7in ideal bir se\u00e7imdir. Ancak, ek bellek kullan\u0131m\u0131 nedeniyle, yerinde s\u0131ralama algoritmalar\u0131 kadar yerden tasarruflu de\u011fildir. Bu durum, b\u00fcy\u00fck veri setlerinde performans\u0131n\u0131 etkileyebilir.<\/p>\n
Algoritma Kar\u015f\u0131la\u015ft\u0131rmas\u0131<\/h2>\n
A\u015fa\u011f\u0131daki tabloda, incelenen algoritmalar\u0131n zaman karma\u015f\u0131kl\u0131klar\u0131n\u0131 \u00f6zetledik:<\/p>\n