
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
"Do you remember Leontina's 40th anniversary? It was December 28, 19## (where ## represents two missing digits). Since then, Leontina has aged. I noticed that half of her age equals twice the sum of its digits."

Please fill in the missing digits in the year of Leontina's 40th anniversary.

Present the answer in LaTex format: \boxed{Your answer}
user