Sort and reserve algorithm

I thought some algorithm what it dose not use built in function. It is sort and reserve algorithm. These are very easy algorithm, Nobody thinks purposely. Moreover, I can not program well and all program language is self learning what I wrote it. So you think that It is trivial program! But it run make me happy.

Sort program

num = [3, 6, 13, 2, 54]
 for i in range(len(num)):
     for j in range(len(num)):
         if num[i] > num[j]:
            tmp = num[i]   
            num[i] = num[j]
            num[j] = tmp

result → [54, 13, 6, 3, 2]

Reserve program

num = [3, 6, 13, 2, 54]
 for i in range(len(num)):
     for j in range(len(num)):
         if num[i] < num[j]:
            tmp = num[i]   
            num[i] = num[j]
            num[j] = tmp

result → [2, 3, 6, 13, 54]