Problem:
Score : 200 points

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?

Constraints

All input values are integers.

1 \leq X, Y, Z \leq 10^5

Y+2Z \leq X

Input

Input is given from Standard Input in the following format:

X Y Z

Output

Print the answer.

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

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

def getNum():
    x,y,z = map(int,input().split())
    return x,y,z

def cal(x,y,z):
    tmp = x / (y+z)
    # print(tmp)
    # print(int(tmp))
    if tmp == int(tmp):
        # print("t")
        print(int(tmp))
    else:
        print(int(tmp) - 1)

def main():
    x,y,z = getNum()
    cal(x,y,z)

main()