Lan Lan's home is 800 meters away from the library. She went out to the library to borrow books. After walking 100 meters, she realized that she had forgotten her library card. How far has Lan Lan traveled during this time?
兰兰家距图书馆800米，她出门前往图书馆借书，走了100米后发现忘了带借书证，连忙回家拿借书证再去图书馆．兰兰这段时间走了多远？
<gadget id="calculator">100 + 100 + 800</gadget>
<output>1_000</output>

<result>1_000</result>