package main

import (
    "testing"
    "math"
)

func TestReverse(t *testing.T) {
    if res := reverse(123); res != 321 {
        t.Fatalf("%v != 321", res)
    }
    if res := reverse(-123); res != -321 {
        t.Fatalf("%v != -321", res)
    }
    if res := reverse(120); res != 21 {
        t.Fatalf("%v != 12", res)
    }
    if res := reverse(math.MaxInt32); res != 0 {
        t.Fatalf("%v != 0", res)
    }
}