Deleting duplicate elements in a array

Question

I am trying to delete duplicate elements in a array. There are lots of methods out there but I am trying to come up with my own one and tried the folllowing code.

x=[2,1,3,5,3,5]
for i in range(0,len(x)):
  for j in range(0,len(x)):
      if (x[i]==x[j+1]):
           del x[j+1]
for k in range(0,len(x)):
    print(x[k])

I get the following error at line 4 list index out of range.

Please help me!

See: https://stackoverflow.com/questions/1207406/how-to-remove-items-from-a-list-while-iterating, the error comes from changing the length of the list while iterating over it — Primusa, Nov 03 '19 at 18:47

score 0 · Accepted Answer · answered Nov 03 '19 at 19:08

There are two errors I can see:

You are using j+1 in your program. When the second for loop reaches the end of the loop, j would equal 5, and then j+1 would equal 6, but x[6] would be out of bounds.
Deleting the element from the array changes the length of the array. For example, your array starts with a length of 6, but then, after one of the elements is deleted, it instead has a length 5. However, the for loop doesn't recognize this, and still goes until i=5 instead of stopping at i=4, and x[5] is out of bounds.

Deleting duplicate elements in a array

1 Answers1