// No.2099 [Cherry Alpha B] Time Machine
package main

import (
	"fmt"
	"math"
)

func main() {
	var T, X, A, B, Y int
	fmt.Scan(&T)
	fmt.Scan(&X, &A)
	fmt.Scan(&Y, &B)

	var t, d int
	if T >= 0 {
		i := T / A
		t = T % A
		d = i * X
	} else {
		i := (-T + B - 1) / B
		t = T + i*B
		d = i * Y
	}

	mind := math.MaxInt
	var f func(t, d int)
	f = func(t, d int) {
		if d > mind {
			return
		}
		if t == 0 {
			if d < mind {
				mind = d
			}
			return
		}

		if t > 0 {
			f(0, d+t)
			f(t-A, d+X)
		} else {
			f(t+B, d+Y)
		}
	}
	f(t, d)
	fmt.Println(mind)
}