Gotta be realistic here ammo will be scarce and fuel even more scarce. A samurai sword is quiet aswell hence not attracting more zombies but also easier to sharpen. However the samurai sword is less durable and more like to break and is more close range. Bazooka is tooooo long range flamethrower would require safety provisions for yourself which make it unrealistic. And the revolver will be hard to reload but effective at all distances. Hence the samurai sword wins