```go
package main

import (
	"fmt"
	"math"
)

func main() {
	var a, v, u, n int
	if _, err := fmt.Scan(&a, &v, &u, &n); err != nil {
		return
	}

	ans := 0
	for i := 0; i < n; i++ {
		var xi, yi int
		fmt.Scan(&xi, &yi)

		var xOpt float64
		if u >= v {
			xOpt = float64(a)
		} else {
			xStar := float64(xi) + math.Abs(float64(yi))*float64(u)/math.Sqrt(float64(v*v-u*u))
			if xStar < 0 {
				xOpt = 0
			} else if xStar > float64(a) {
				xOpt = float64(a)
			} else {
				xOpt = xStar
			}
		}

		dist := math.Sqrt((xOpt-float64(xi))*(xOpt-float64(xi)) + float64(yi)*float64(yi))
		tc := dist / float64(u)
		tm := xOpt / float64(v)

		if tc <= tm+1e-9 {
			ans++
		}
	}
	fmt.Println(ans)
}
```