如何在python的循环中移至循环的下一个迭代？

Question

Take for example the code below with 2 for loops.

for xy in set:
        for name in dict:
            if xy == name:
               print("Yay")

What I'm wondering is, if after the if statement is found to be true, will it keep iterating through 'dict' or will it go back upto the first for loop and move onto the next iteration? I can't believe how long I've been using python and I don't know the answer to such a simple question.

Thanks!

Answer 1

It will continue to iterate in dict. If you want to jump out of the inner loop, use break .

You can also try.

if any(name in dict for name in set):
    print('Yay')

Answer 2

It keep iterate through dict .

If you want the loop go back upto first for loop, use break statement :

for xy in set:
    for name in dict:
        if xy == name:
           print("Yay")
           break

As Jacob Krall commented, You don't need to iterate the dictionary object to check whether key( name ) exist. Use in operator:

>>> d = {'sam': 'Samuel', 'bob': 'Robert'}
>>> 'bob' in d
True
>>> 'tom' in d
False

---

for xy in set:
    if name in dict:
        print("Yay")

If you want print Yay only once, use set.isdisjoint :

if not set.isdisjoint(dict):
    print("Yay")

BTW, do not use set or dict as variable name. It shadows builtin function set , dict .

Answer 3

It will continue to iterate over dict . If you do not want this behavior try this:

for xy in set:
    for name in dict:
        if xy == name:
           print("Yay")
           break