import java.util.*

fun main(args:Array<String>){
    val (x,y,z) = readLine()!!.split(" ").map{it.toInt()}
    var ans = 0
    var k = x - z * 2
    while(true){
        k -= y
        if(k >= 0) ans++
        else break
        k -= z
    }
    println(ans)
}
