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: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;

class Procon
{
    public Procon() { }
    static void Main(string[] agrs)
    {
        new Procon().Do();
    }

    Scanner cin;

    public void Do()
    {
        cin = new Scanner();
        int X = cin.nextInt();
        int Y = cin.nextInt();
        int Z = cin.nextInt();


        int max = 0;
        while(true) {
            int tmp = max * Y + Z * (max + 1);
            if (tmp > X) {
                Console.WriteLine(max -1);
                return;
            }
            max ++;
        }
    }
}

class Scanner
{
    string[] s;
    int i;
    int max_i;

    public Scanner()
    {
        s = new string[0];
        max_i = 0;
        i = 0;
    }

    public string nextString()
    {
        if (i >= s.Length)
        {
            s = Console.ReadLine().Split(' ');
            max_i = s.Length;
            i = 0;
            if (max_i == 0)
            {
                return "";
            }
            return s[i++];
        }
        else
        {
            return s[i++];
        }
    }

    public int nextInt()
    {
        return int.Parse(nextString());
    }


    public long nextLong()
    {
        return long.Parse(nextString());
    }

    public double nextDouble()
    {
        return double.Parse(nextString());
    }

    public string[] arrayString()
    {
        return Console.ReadLine().Split(' ');
    }

    public int[] arrayInt()
    {
        string[] str = Console.ReadLine().Split(' ');
        int[] array = new int[str.Length];
        for (int i = 0; i < str.Length; i++)
        {
            array[i] = int.Parse(str[i]);
        }
        return array;
    }

    public long[] arrayLong()
    {
        string[] str = Console.ReadLine().Split(' ');
        long[] array = new long[str.Length];
        for (int i = 0; i < str.Length; i++)
        {
            array[i] = long.Parse(str[i]);
        }
        return array;
    }

    public double[] arrayDouble()
    {
        string[] str = Console.ReadLine().Split(' ');
        double[] array = new double[str.Length];
        for (int i = 0; i < str.Length; i++)
        {
            array[i] = double.Parse(str[i]);
        }
        return array;
    }
}