Magic Trick（水题）

Description

Your friend has come up with a math trick that supposedly will blow your mind. Intrigued, youask your friend to explain the trick.

First, you generate a random positive integer k between 1 and 100. Then, your friend will giveyou n operations to execute. An operation consists of one of the four arithmetic operations ADD,SUBTRACT, MULTIPLY, or DIVIDE, along with an integer-valued operand x. You are supposed toperform the requested operations in order.

You don’t like dealing with fractions or negative numbers though, so if during the process, theoperations generate a fraction or a negative number, you will tell your friend that he messed up.

Now, you know the n operations your friend will give. How many of the first 100 positiveintegers will cause your friend to mess up?

Input

The first line of input contains a single positive integer n (1 ≤ n ≤ 10). Each of the next n linesconsists of an operation, followed by an operand. The operation is one of the strings ADD, SUBTRACT,MULTIPLY, or DIVIDE. Operands are positive integes not exceeding 5.

Output

Print, on a single line, a single integer indicating how many of the first 100 positive integers willresult in you telling your friend that he messed up.

Sample Input

1

SUBTRACT 5

Sample Output

4

Sample Input

1

DIVIDE 2

Sample Output

50

Sample Input

2

ADD 5

DIVIDE 5

Sample Output

80

题解：当时做的时候没理解题意，一直w，后来一看，真简单......，就是每一步执行都把小数和负数排除，最后求和。

代码如下：