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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using static System.Console;

class Program {
    static void Main(string[] args) {
        int X = 0;
        int Y = 0;
        int Z = 0;
        string st = ReadLine();
        int cnt = 0;
        int wherespace = 0;
        for (int i = 0; i < 2; i++) {
            wherespace = st.IndexOf(' ', cnt);
            string aS = st.Substring(cnt, wherespace - cnt);
            switch (i) {
                case 0:
                    X = Convert.ToInt32(aS);
                    break;
                case 1:
                    Y = Convert.ToInt32(aS);
                    break;
                case 2:
                    Z = Convert.ToInt32(aS);
                    break;
            }
            cnt = wherespace + 1;
        }
        Z = Convert.ToInt32(st.Substring(cnt - 1, st.Length - (cnt - 1)));

        int amount = 0;
        for (int ci = Z; ci < X; X+=0) {
            ci += Y;
            ci += Z;
            if (ci >= X) {
                break;
            }
            amount++;
        }
        Console.WriteLine(amount.ToString());
    }
}