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Python3&資料結構之選擇排序

第一種寫法:來自演算法圖解

def findSmallest(arr):
    smallest = arr[0]
    smallest_index = 0
    for i in range(1,len(arr)):
        if arr[i] < smallest:
            smallest = arr[i]
            smallest_index = i
    return smallest_index

def selectionSort(arr):
    newArr = []
    for i in range(len(arr)):
        smallest = findSmallest(arr)
        newArr.append(arr.pop(smallest))
    return newArr

if __name__ == '__main__':
    test = [49, 38, 65, 97, 76, 13, 27, 49]
    print(selectionSort(test))

第二種寫法:

def select_sort(arr):
    for i in range(len(arr)):
        m = i
        for j in range(i,len(arr)):
            if arr[j]<arr[m]:
                m = j
        arr[i],arr[m] = arr[m],arr[i]
    return arr

if __name__ == '__main__':
    test = [49, 38, 65, 97, 76, 13, 27, 49]
    print(select_sort(test))

時間複雜度:O(n^2)