the code is as follows:
s = ["adam", "xxx", "lisa"]
L = ["adam", "xxx", "lisa", "bart"]
for x in L:
print "this is ---%s" % x
if x in s:
print x
L.remove(x)
print L
the results are as follows:
this is-adam
adam
this is-lisa
lisa
["xxx"," bart"]
[Finished in 0.2s]
Why is" xxx" directly ignored?
the program runs as follows
Loop 1 br x points to adam: in L
print this is-adam
print adam
removes the adam,x in L pointing to xxx in L
cycle is over, x continues to go down, pointing to lisa in L
Loop 2 lisa
print this is-lisa
print lisa
remove the lisa,x in L pointing to bart in L
cycle is over, x continues to go down, can't go down, the whole cycle ends
is not ignored, but the position has changed
Let's see if you can understand it ( python3 ):
s = ["adam", "xxx", "lisa"]
L = ["adam", "xxx", "lisa", "bart"]
for x in L[:]:
print("this is ---%s" % x)
if x in s:
print(x)
L.remove(x)
print(L)
output
this is ---adam
adam
this is ---xxx
xxx
this is ---lisa
lisa
this is ---bart
['bart']
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