var a = big.NewInt(math.MaxInt64)
//a is 9223372036854775807
fmt.Println("a =", a)
var b = big.NewInt(255)
var c = big.NewInt(1000)
a = a.Mul(a, c)
//a is 9223372036854775807000
fmt.Println("a =", a)
a = a.Add(a, c).Quo(a, b)
//a is 36170086419038336501
fmt.Println("a =", a)