Issue 523, Boyer Moore Horspool String Search walked off end the array in the case where a needle was not in the haystack but it's component characters still existed in the haystuck thus not triggereing the initial short circuit

panderson54 · panderson54 · commit e53d24bd9e88 · 2018-02-10T17:41:13.000-07:00
diff --git a/Boyer_Moore_Horspool/C#/Davipb/Horspool.cs b/Boyer_Moore_Horspool/C#/Davipb/Horspool.cs
@@ -32,7 +32,7 @@ public static int Find(string haystack, string needle)
 
 			int index = 0;
 
-			while (index <= haystack.Length - needle.Length)
+			while (index < haystack.Length - needle.Length)
 			{
 				bool match = true;
 
@@ -42,6 +42,10 @@ public static int Find(string haystack, string needle)
 					{
 						match = false;
 						index += BadMatchTable[haystack[index + needle.Length - 1]];
+						if (index >= haystack.Length)
+                        {
+                            break;
+                        }
 					}
 				}
 

Original file line number	Diff line number	Diff line change
`@@ -32,7 +32,7 @@ public static int Find(string haystack, string needle)`
`32`	`32`
`33`	`33`	`int index = 0;`
`34`	`34`
`35`		`- while (index <= haystack.Length - needle.Length)`
	`35`	`+ while (index < haystack.Length - needle.Length)`
`36`	`36`	`{`
`37`	`37`	`bool match = true;`
`38`	`38`
`@@ -42,6 +42,10 @@ public static int Find(string haystack, string needle)`
`42`	`42`	`{`
`43`	`43`	`match = false;`
`44`	`44`	`index += BadMatchTable[haystack[index + needle.Length - 1]];`
	`45`	`+ if (index >= haystack.Length)`
	`46`	`+ {`
	`47`	`+ break;`
	`48`	`+ }`
`45`	`49`	`}`
`46`	`50`	`}`
`47`	`51`