import "math/big"

var a bigint = 1r << 65 // bigint, large than int64
var b bigrat = 4/5r     // bigrat
c := b - 1/3r + 3*1/2r // bigrat
println(a, b, c)

var x *big.Int = 1r << 65 // (1r << 65) is untyped bigint, and can be assigned to *big.Int
var y *big.Rat = 4/5r
println(x, y)

a = new(big.Int).Abs(-265r)
println("abs(-265r):", a)