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pythonnested-loops

The same variable in Python Nested-loops has different IDs？

very simple Python code, but why the variable n has different IDs？ How can I implement this function to get car's dictionary name?

a = [{'a':['apple','animal']},{'b':['banana']},{'c':['class','car']}]
n = 0
while n < 3:
    print(id(n))
    for k in a[n].keys():
        if 'car' not in a[n][k]:
            n += 1
            print(id(n))
        else:
            print(k)
            break
    break

The result of the code is:

140720577618304
140720577618336
Solution

  • an integer in Python is immutable. By doing n+=1, you're not modifying the object called n, you're overwriting the name to point to a new integer object.