diff --git a/.project b/.project
index 3cd55b5c..86e73f4a 100644
--- a/.project
+++ b/.project
@@ -14,4 +14,15 @@
org.eclipse.jdt.core.javanature
+
+
+ 1730486790075
+
+ 30
+
+ org.eclipse.core.resources.regexFilterMatcher
+ node_modules|\.git|__CREATED_BY_JAVA_LANGUAGE_SERVER__
+
+
+
diff --git a/src/com/jwetherell/algorithms/mathematics/Division.class b/src/com/jwetherell/algorithms/mathematics/Division.class
new file mode 100644
index 00000000..9f83cecf
Binary files /dev/null and b/src/com/jwetherell/algorithms/mathematics/Division.class differ
diff --git a/src/com/jwetherell/algorithms/mathematics/Division.java b/src/com/jwetherell/algorithms/mathematics/Division.java
index c133f741..397e7bbe 100644
--- a/src/com/jwetherell/algorithms/mathematics/Division.java
+++ b/src/com/jwetherell/algorithms/mathematics/Division.java
@@ -4,54 +4,75 @@ public class Division {
public static final long division(int a, int b) {
long result = ((long) a) / ((long) b);
+
+ if (b == 0) {
+ throw new IllegalArgumentException ("Divisor cannot be 0");
+ }
+ else {
return result;
+ }
}
public static final long divisionUsingLoop(int a, int b) {
int absA = Math.abs(a);
int absB = Math.abs(b);
- long temp = absA;
- long result = 0;
- while (temp >= 0) {
- temp -= absB;
- if (temp >= 0)
- result++;
- }
- return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ if (b == 0) {
+ throw new IllegalArgumentException ("Divisor cannot be 0");
+ }
+ else {
+ long temp = absA;
+ long result = 0;
+ while (temp >= 0) {
+ temp -= absB;
+ if (temp >= 0)
+ result++;
+ }
+ return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ }
}
public static final long divisionUsingRecursion(int a, int b) {
int absA = Math.abs(a);
int absB = Math.abs(b);
- long result = 1;
- int diff = absA - absB;
- if (diff > 0 && diff <= 1) {
- return result;
- } else if (diff < 0) {
- return 0;
- }
+ if (b == 0) {
+ throw new IllegalArgumentException ("Divisor cannot be 0");
+ }
+ else {
+ long result = 1;
+ int diff = absA - absB;
+ if (diff > 0 && diff <= 1) {
+ return result;
+ } else if (diff < 0) {
+ return 0;
+ }
- result += divisionUsingRecursion(diff, absB);
- return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ result += divisionUsingRecursion(diff, absB);
+ return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ }
}
public static final long divisionUsingMultiplication(int a, int b) {
int absA = Math.abs(a);
int absB = Math.abs(b);
- int temp = absB;
- int counter = 0;
- while (temp <= absA) {
- temp = temp << 1;
- counter++;
- }
- absA -= absB << (counter - 1);
- long result = (long) Math.pow(2, counter - 1);
- if (absB <= absA)
- result += divisionUsingMultiplication(absA, absB);
- return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ if (b == 0) {
+ throw new IllegalArgumentException ("Divisor cannot be 0");
+ }
+ else {
+ int temp = absB;
+ int counter = 0;
+ while (temp <= absA) {
+ temp = temp << 1;
+ counter++;
+ }
+ absA -= absB << (counter - 1);
+ long result = (long) Math.pow(2, counter - 1);
+ if (absB <= absA)
+ result += divisionUsingMultiplication(absA, absB);
+ return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ }
}
public static final long divisionUsingShift(int a, int b) {
@@ -59,29 +80,40 @@ public static final long divisionUsingShift(int a, int b) {
int absB = Math.abs(b);
int tempA, tempB, counter;
- long result = 0L;
- while (absA >= absB) {
- tempA = absA >> 1; // Right shift "a"
- tempB = absB;
- counter = 1;
- while (tempA >= tempB) { // Double "tempB" until it's larger than
- // "tempA"
- tempB <<= 1;
- counter <<= 1; // Double the counter
- }
- absA -= tempB; // Subtract "tempB" from "a"
- result += counter; // Add counter (2^number of left shifts)
- }
- return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ if (b == 0) {
+ throw new IllegalArgumentException ("Divisor cannot be 0");
+ }
+ else {
+ long result = 0L;
+ while (absA >= absB) {
+ tempA = absA >> 1; // Right shift "a"
+ tempB = absB;
+ counter = 1;
+ while (tempA >= tempB) { // Double "tempB" until it's larger than
+ // "tempA"
+ tempB <<= 1;
+ counter <<= 1; // Double the counter
+ }
+ absA -= tempB; // Subtract "tempB" from "a"
+ result += counter; // Add counter (2^number of left shifts)
+ }
+ return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ }
}
public static final long divisionUsingLogs(int a, int b) {
long absA = Math.abs(a);
long absB = Math.abs(b);
- double logBase10A = Math.log10(absA);
- double logBase10B = Math.log10(absB);
- double powOf10 = Math.pow(10, (logBase10A - logBase10B));
- long result = (long) Math.floor(powOf10);
- return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+
+ if (b == 0) {
+ throw new IllegalArgumentException ("Divisor cannot be 0");
+ }
+ else {
+ double logBase10A = Math.log10(absA);
+ double logBase10B = Math.log10(absB);
+ double powOf10 = Math.pow(10, (logBase10A - logBase10B));
+ long result = (long) Math.floor(powOf10);
+ return (a > 0 && b > 0 || a < 0 && b < 0) ? result : -result;
+ }
}
}