Recursively push the 2456 numbers one by one from the ones to the thousands into the stack
After the push is completed, the unstack begins. The unstack sequence is 2 4 5 6. During the unstack process, '1' is added to each bit, that is, 1 is added when displayed
The result is 3567
What should be examined is the understanding of the recursive stack
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Recursively push the 2456 numbers one by one from the ones to the thousands into the stack
After the push is completed, the unstack begins. The unstack sequence is 2 4 5 6. During the unstack process, '1' is added to each bit, that is, 1 is added when displayed
The result is 3567
What should be examined is the understanding of the recursive stack