From 7fdae4285b88bf65f176886eca10a09860adece3 Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Mon, 24 Jul 2017 13:44:09 -0700
Subject: [PATCH] Fix copy pasting in NaiveNumber.

---
 src/org/nwapw/abacus/number/NaiveNumber.java | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/src/org/nwapw/abacus/number/NaiveNumber.java b/src/org/nwapw/abacus/number/NaiveNumber.java
index b63008d..10b89a4 100644
--- a/src/org/nwapw/abacus/number/NaiveNumber.java
+++ b/src/org/nwapw/abacus/number/NaiveNumber.java
@@ -15,26 +15,22 @@ public class NaiveNumber implements Number {
 
     @Override
     public Number multiply(Number multiplier) {
-        if(!(multiplier instanceof NaiveNumber)) throw new IllegalArgumentException();
         return new NaiveNumber(value * ((NaiveNumber)multiplier).value);
     }
 
     @Override
     public Number divide(Number divisor) {
-        if(!(divisor instanceof NaiveNumber)) throw new IllegalArgumentException();
-        return new NaiveNumber(value * ((NaiveNumber)divisor).value);
+        return new NaiveNumber(value / ((NaiveNumber)divisor).value);
     }
 
     @Override
     public Number add(Number summand) {
-        if(!(summand instanceof NaiveNumber)) throw new IllegalArgumentException();
-        return new NaiveNumber(value * ((NaiveNumber)summand).value);
+        return new NaiveNumber(value + ((NaiveNumber)summand).value);
     }
 
     @Override
     public Number subtract(Number subtrahend) {
-        if(!(subtrahend instanceof NaiveNumber)) throw new IllegalArgumentException();
-        return new NaiveNumber(value * ((NaiveNumber)subtrahend).value);
+        return new NaiveNumber(value - ((NaiveNumber)subtrahend).value);
     }
 
     @Override