Problem Statement

We have a long seat of width X centimeters.
There are many people who wants to sit here. A person sitting on the seat will always occupy an interval of length Y centimeters.
We would like to seat as many people as possible, but they are all very shy, and there must be a gap of length at least Z centimeters between two people, and between the end of the seat and a person.
At most how many people can sit on the seat?

Input

Input is given from Standard Input in the following format:
X Y Z

Output

Print the answer.

Constraints

• All input values are integers.
• $1 \leq X, Y, Z \leq 10^5$
• $Y+2Z \leq X$

Sample Input 1

13 3 1

Sample Output 1

3

There is just enough room for three, as shown below:

Figure

Sample Input 2

12 3 1

Sample Output 2

2

Sample Input 3

100000 1 1

Sample Output 3

49999

Sample Input 4

64146 123 456

Sample Output 4

110

Sample Input 5

64145 123 456

Sample Output 5

109

见题面 Input 部分

见题面 Output 部分