Use the five numbers 1, 2, 3, 4, and 5 to form a five-digit number with different numbers in each digit. How many such five-digit numbers are there?
用1、2、3、4、5这五个数字组成各个数位上数字都不相同的五位数，这样的五位数共有多少个？
<gadget id="calculator">5 * 4 * 3 * 2 * 1</gadget>
<output>120</output>

<result>120</result>