l = ["1", "2", "1", "1"]
for i in l:
if i == "1":
i = "3"
print(l)Why is the result of l still ["1percent," 2percent, "1percent," 1"], and how can it be modified to ["3percent," 2percent, "3percent," 3"]?
l = ["1", "2", "1", "1"]
for i in l:
if i == "1":
i = "3"
print(l)Why is the result of l still ["1percent," 2percent, "1percent," 1"], and how can it be modified to ["3percent," 2percent, "3percent," 3"]?
l = ['1percent,' 2percent, '1percent,' 1']
new_l = []
for i in l:
if i == '1':
new_l.append(3)
else:
new_l.append(i) l = new_l
print (l)
-sharp
for i in range(len(l)):
if l[i] == '1':
l[i] = '3'
-sharp
for i, item in enumerate(l):
if item == '1':
l[i] = '3'
in addition, if you want to delete an element, it is recommended not to make changes directly on the original data. It is prudent to make a copy list.remove (value) to delete.
-sharp
for idx, i in enumerate(l):
if i == '1':
l[idx] = '3'
-sharp
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