How many terms are there in the arithmetic sequence 1, 3, 5, ..., 197, 199?
等差数列1、3、5、…、197、199共有多少项？
<gadget id="calculator">199 - 1</gadget>
<output>198</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">198 / 2</gadget>
<output>99</output>

<gadget id="calculator">99 + 1</gadget>
<output>100</output>

<result>100</result>