String deduplication

1. Use collections — not in the same order

print(set(pstr))
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2. Use a dictionary — not in the same order

print({}.fromkeys(pstr).keys())
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3. Use loop traversal — the code is not clean enough or high end

a = []
for i in range(len(pstr)):
    if pstr[i] not in a:
        a.append(pstr[i])
print(a)
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List to heavy

plist = [1.0.3.7.5.7]
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1. Use the set method

print(list(set(plist)))
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2. Use a dictionary

print(list({}.fromkeys(plist).keys()))
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3. Cycle traversal

#Python Learning Exchange group: 531509025

plist1 = []
for i in plist:
    if i not in plist1:
        plist1.append(i)
print(plist1)
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4. Sort by index again

b = list(set(plist))
b.sort(key=plist.index)
print('sds:',b)
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