Add maximum subarray function

README.md

@@ -2,14 +2,15 @@
 
   This is a collection of different algorithms, written in JavaScript.
   The purpose of this package is to define basic algorithms in a concise,
-  but readable form. However, no (pre)mature optimizations should be expected 
+  but readable form. However, no (pre)mature optimizations should be expected
   here and code should never be used in production.
 
 ## Contents
 
 ### Iterative
 
   - [x] coprime
+  - [x] maxsubarray
   - [x] prime
 
 ### Recursive

lib/iterative/maxsubarray.js

@@ -0,0 +1,18 @@
+
+/**
+ * Expose `maxsubarray`.
+ */
+
+module.exports = maxsubarray;
+
+function maxsubarray(array) {
+  var maximum = 0;
+  var current = 0;
+
+  for (var i = 0; i < array.length; i++) {
+    current = Math.max(0, current + array[i]);
+		maximum = Math.max(maximum, current);
+  }
+
+  return maximum;
+}

lib/iterative/test/maxsubarray-test.js

@@ -0,0 +1,7 @@
+var test = require('tape');
+var maxsubarray = require('../maxsubarray');
+
+test('prime(number)', function (t) {
+  t.equal(maxsubarray([-2, 1, -3, 4, -1, 2, 1, -5, 4]), 6, 'should be equal 6');
+  t.end();
+});