Implement longestRun.js

longestRun/longestRun.js

@@ -12,7 +12,32 @@
  */
 
 var longestRun = function (string) {
-  // TOD: Your code here!
+  var strLen = string.length;
+  if (strLen === 0) return [];
+  if (strLen === 1) return [0, 0];
+
+  // strings of length 2 or greater
+  var currentStart  = 0;
+  var currentLength = 1;
+  var maxStart  = 0;
+  var maxLength = 1;
+  var i;
+
+  for (i = 1; i < strLen; i += 1) {
+    // check if this character is the same as previous character
+    if ( string[i] === string[i - 1] ) {
+      currentLength += 1;
+    } else {
+      if (currentLength > maxLength) {
+        maxStart  = currentStart;
+        maxLength = currentLength;
+      }
+      currentStart  = i;
+      currentLength = 1;
+    }
+  }
+
+  return [ maxStart, maxStart + maxLength - 1 ];
 };
 
 // If you need a random string generator, use this!