package main

import (
    "fmt"
)

func main() {
    var (
        vx float64 = 0
        vy float64 = -1
        vz float64 = vx*vy
    )
    fmt.Println("var:  ", vz)

    const (
        cx float64 = 0
        cy float64 = -1
        cz float64 = cx*cy
    )
    fmt.Println("const: ", cz)
}

var:   -0
const:  0