From 4146e1a439d812d97055bb5967f05fb12210e871 Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Sat, 5 Aug 2017 18:22:43 -0700
Subject: [PATCH] Revert "Remove the NumberInterface::intPow method."

0c16bb4e9be6d6b51dd87e9c6cc8d6040cdf679f
---
 .../org/nwapw/abacus/number/NaiveNumber.java  | 17 +++++++++++++++
 .../nwapw/abacus/number/NumberInterface.java  | 21 +++++++++++++++++++
 .../nwapw/abacus/number/PreciseNumber.java    | 17 +++++++++++++++
 .../nwapw/abacus/plugin/StandardPlugin.java   |  6 ++----
 4 files changed, 57 insertions(+), 4 deletions(-)

diff --git a/src/main/java/org/nwapw/abacus/number/NaiveNumber.java b/src/main/java/org/nwapw/abacus/number/NaiveNumber.java
index 5326eb4..48beb1a 100755
--- a/src/main/java/org/nwapw/abacus/number/NaiveNumber.java
+++ b/src/main/java/org/nwapw/abacus/number/NaiveNumber.java
@@ -66,6 +66,23 @@ public class NaiveNumber extends NumberInterface {
         return new NaiveNumber(-value);
     }
 
+    @Override
+    public NumberInterface intPowInternal(int exponent) {
+        if (exponent == 0) {
+            return NaiveNumber.ONE;
+        }
+        boolean takeReciprocal = exponent < 0;
+        exponent = Math.abs(exponent);
+        NumberInterface power = this;
+        for (int currentExponent = 1; currentExponent < exponent; currentExponent++) {
+            power = power.multiply(this);
+        }
+        if (takeReciprocal) {
+            power = NaiveNumber.ONE.divide(power);
+        }
+        return power;
+    }
+
     @Override
     public int compareTo(NumberInterface number) {
         NaiveNumber num = (NaiveNumber) number;
diff --git a/src/main/java/org/nwapw/abacus/number/NumberInterface.java b/src/main/java/org/nwapw/abacus/number/NumberInterface.java
index f5f1f72..7af5901 100755
--- a/src/main/java/org/nwapw/abacus/number/NumberInterface.java
+++ b/src/main/java/org/nwapw/abacus/number/NumberInterface.java
@@ -134,6 +134,27 @@ public abstract class NumberInterface {
         return negateInternal();
     }
 
+    /**
+     * Raises this number to an integer power.
+     *
+     * @param exponent the exponent to which to take the number.
+     * @return the resulting value.
+     */
+    protected abstract NumberInterface intPowInternal(int exponent);
+
+    /**
+     * Raises this number to an integer power. Also, checks if the
+     * thread has been interrupted, and if so, throws
+     * an exception.
+     *
+     * @param exponent the exponent to which to take the number.
+     * @return the resulting value.
+     */
+    public final NumberInterface intPow(int exponent){
+        checkInterrupted();
+        return intPowInternal(exponent);
+    }
+
     /**
      * Compares this number to another.
      *
diff --git a/src/main/java/org/nwapw/abacus/number/PreciseNumber.java b/src/main/java/org/nwapw/abacus/number/PreciseNumber.java
index 2b4a8e1..abc657f 100755
--- a/src/main/java/org/nwapw/abacus/number/PreciseNumber.java
+++ b/src/main/java/org/nwapw/abacus/number/PreciseNumber.java
@@ -71,6 +71,23 @@ public class PreciseNumber extends NumberInterface {
         return new PreciseNumber(value.subtract(((PreciseNumber) subtrahend).value));
     }
 
+    @Override
+    public NumberInterface intPowInternal(int exponent) {
+        if (exponent == 0) {
+            return PreciseNumber.ONE;
+        }
+        boolean takeReciprocal = exponent < 0;
+        exponent = Math.abs(exponent);
+        NumberInterface power = this;
+        for (int currentExponent = 1; currentExponent < exponent; currentExponent++) {
+            power = power.multiply(this);
+        }
+        if (takeReciprocal) {
+            power = PreciseNumber.ONE.divide(power);
+        }
+        return power;
+    }
+
     @Override
     public int compareTo(NumberInterface number) {
         return value.compareTo(((PreciseNumber) number).value);
diff --git a/src/main/java/org/nwapw/abacus/plugin/StandardPlugin.java b/src/main/java/org/nwapw/abacus/plugin/StandardPlugin.java
index f926c20..c123caa 100755
--- a/src/main/java/org/nwapw/abacus/plugin/StandardPlugin.java
+++ b/src/main/java/org/nwapw/abacus/plugin/StandardPlugin.java
@@ -311,9 +311,7 @@ public class StandardPlugin extends Plugin {
                 //right and left refer to lhs and rhs in the above inequality.
                 NumberInterface sum = NaiveNumber.ONE.promoteTo(params[0].getClass());
                 NumberInterface nextNumerator = params[0];
-                NumberInterface left = params[0].multiply((new NaiveNumber(3)).promoteTo(params[0].getClass()));
-                left = intPow(left, left.getClass(), new NaiveNumber(params[0].ceiling().intValue()).promoteTo(left.getClass()));
-                NumberInterface right = maxError;
+                NumberInterface left = params[0].multiply((new NaiveNumber(3)).promoteTo(params[0].getClass()).intPow(params[0].ceiling().intValue())), right = maxError;
                 do {
                     sum = sum.add(nextNumerator.divide(factorial(params[0].getClass(), n + 1)));
                     n++;
@@ -472,7 +470,7 @@ public class StandardPlugin extends Plugin {
      * @return the maximum error.
      */
     private static NumberInterface getMaxError(NumberInterface number) {
-        return intPow(new NaiveNumber(10).promoteTo(number.getClass()), number.getClass(), new NaiveNumber(-number.getMaxPrecision()).promoteTo(number.getClass()));
+        return (new NaiveNumber(10)).promoteTo(number.getClass()).intPow(-number.getMaxPrecision());
     }
 
     /**