package main

import (
 "fmt"
)

func Gcd(x int64, y int64) int64 {
 if y == 0 {
  return x
 } else {
  return Gcd(y, x%y)
 }
}

func main() {
 var x, y, gcd, ans int64
 fmt.Scan(&ans, &gcd)
 f := 0
 for i := 0; i < 2; i++ {
  fmt.Scan(&x, &y)
  j := int64(0)
  for ; ans == 0 || (ans%y != x && j < y); j++ {
   ans += gcd
  }
  if j == y {
   f = 1
  }
  gcd = gcd * y / Gcd(gcd, y)
 }
 if f == 1 {
  fmt.Println(-1)
 } else {
  fmt.Println(ans)
 }
}