Order a list of numbers without built-in sort, min, max function

user_1589244 0
Viewed 228952

If I have a list that varies in length each time and I want to sort it from lowest to highest, how would I do that?

If I have: [-5, -23, 5, 0, 23, -6, 23, 67]

I want: [-23, -6, -5, 0, 5, 23, 23, 67]

I start with this: 

data_list = [-5, -23, 5, 0, 23, -6, 23, 67]

new_list = []

minimum = data_list[0]  # arbitrary number in list 

for x in data_list: 
  if x < minimum:
    minimum = value
    new_list.append(i)

BUT this only goes through once and I get: 

new_list = [-23]

This is where I get stuck.

How do I keep looping through until the len(new_list) = len(data_list) (i.e. all the numbers are in the new list) with everything sorted without using the built in max, min, sort functions? I'm not sure if it's necessary to create a new list either.

for-loop sorting python
24 Answers

This works!

def sorting(li):
    for i in range(len(li)):
        for j in range(len(li)):
            if li[i] < li[j]:
                li[j],li[i] = li[i],li[j]
    return li

listToSort = [22,11,23,1,100,24,3,101,2,4]
print(sorting(listToSort))
user_98224220 
data = [3, 1, 5, 2, 4]
n = len(data)
    for i in range(n):
        for j in range(1,n):
            if data[j-1] > data[j]:
                (data[j-1], data[j]) = (data[j], data[j-1])
    print(data)
user_89484110 
# Your current setup
data_list = [-5, -23, 5, 0, 23, -6, 23, 67]
new_list  = []

# Sort function
for i in data_list:
    new_list = [ x for x in new_list if i > x ] + [i] + [ x for x in new_list if i <= x ]
user_61636210

You could do it easily by using min() function

`def asc(a):
    b=[]
    l=len(a)
    for i in range(l):
        x=min(a)
        b.append(x)
        a.remove(x)
    return b
 print asc([2,5,8,7,44,54,23])`
user_103067430 
n = int(input("Input list lenght: "))
lista = []
for i in range (1,n+1):
    print ("A[",i,"]=")
    ele = int(input())
    lista.append(ele)
print("The list is: ",lista)
invers = True
while invers == True:
    invers = False 
    for i in range (n-1):
        if lista[i]>lista[i+1]:
            c=lista[i+1]
            lista[i+1]=lista[i]
            lista[i]=c
            invers = True
print("The sorted list is: ",lista)
user_122260660

Swapping the values from 1st position to till the end of the list, this code loops for ( n*n-1)/2 times. Each time it pushes the greater value to the greater index starting from Zero index.

list2 = [40,-5,10,2,0,-4,-10]
for l in range(len(list2)):
    for k in range(l+1,len(list2)):
        if list2[k] < list2[l]:
            list2[k] , list2[l] = list2[l], list2[k]
print(list2)
user_59560170

Since complexity doesn’t matter, I present to you...BogoSort:

from random import shuffle

def is_sorted(ls):
    for idx in range(len(ls)-1):
        if x[idx] > x[idx + 1]:
          return False
    return True

def sort(ls):
    while not is_sorted(ls):
        shuffle(ls)
    return ls


ls = list(range(5))
shuffle(ls)

print(
    "Original: ",
    ls
)

print(
    "Sorted: ",
    sorted(ls)
)
user_106396940

This is the unsorted list and we want is 1234567

list = [3,1,2,5,4,7,6]

def sort(list):
    for i in range(len(list)-1):
        if list[i] > list[i+1]:
            a = list[i]
            list[i] = list[i+1]
            list[i+1] = a
        print(list)       

sort(list)

simplest in simplest method to sort a array. Im using currently bubble sorting that is: it checks first 2 location and moves the smallest number to left so on. "-n"in loop is to avoid the indentation error you will understand it by doing it so.

user_150549450

You can used iterative approach one by one comparing along with recursive function. The result in ascending order if you want descending order then change the condition from if l[i]>l[i+1] to if l[i]<l[i+1]:

l=[2,1,3,4,3,2,1,2] 
list_len=len(l)

def fun(l):
    for i in range(list_len):
        if i<list_len-1:
            if l[i]>l[i+1]:
                l[i],l[i+1]=l[i+1],l[i]
                fun(l)
    return l
            
print(fun(l))
user_162746210 
for i in range (0, len(unsorted_list)):
    for j in range (i,  len(unsorted_list)):
        if unsorted_list[i]> unsorted_list[j]:
            unsorted_list[i], unsorted_list[j] = unsorted_list[j], unsorted_list[i]

print("Sorted list: ", unsorted_list)

output is: Sorted list: [0, 5, 9, 10, 11, 20, 100, 100]

Time complexity is Quadratic time – O (n^2)

user_17951100

Use this with for loop

    arr = [1, 5, 0, 0, 9, 10, 9, 3, 2, 3, 5,10]
    new_arr = []
    for index in range(len(arr)):
        index = len(new_arr) - index
        max_val = arr[index]
        for val in arr[index+1:]:
            if val >= max_val:
                max_val = val
        new_arr.append(max_val)
        arr.remove(max_val)
    print(new_arr)

Use this with while loop

    arr = [1, 5, 0, 0, 9, 10, 9, 3, 2, 3, 5,10]
    new_arr = []
    while arr:
        max_val = arr[0]
        for x in arr:
            if x >= max_val:
                max_val = x
        new_arr.append(max_val)
        arr.remove(max_val)
    
    print(new_arr)

With function,for ASC use reverse = 1 and -1 for DESC

    def custom_sorting(numbers, new_list, reverse=-1):
        for i in range(len(numbers)):
            first_num = numbers[0]
            for num in numbers:
                if num < first_num and reverse < 0:
                    first_num = num
                if num > first_num and reverse > 0:
                    first_num = num
    
            numbers.remove(first_num)
            new_list.append(first_num)
    
    
    if __name__ == "__main__":
        data = [5, 4, 2, 8, 70, 0, 0, 96, 5]
        newlist = []
        custom_sorting(data, newlist, reverse=1)
        print(newlist)```
user_173935180
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