fix bug of boyer-moore

biaodigit · biaodigit · commit 85120517b646 · 2018-10-16T21:30:54.000+08:00
diff --git a/Classical algorithm problem/Boyer-Moore.html b/Classical algorithm problem/Boyer-Moore.html
@@ -6,12 +6,10 @@
 </head>
 <body>
 <script>
-    const MAX_CHAR_SIZE = 256;
-
-    function BoyerMoore(text, pattern,) {
+    function BoyerMoore(text, pattern) {
         let tLen = text.length,
             pLen = pattern.length,
-            lastArr = Array(MAX_CHAR_SIZE),
+            lastArr = [],
             matchArr = Array(pLen),
             suffixArr = Array(pLen);
 
@@ -31,7 +29,7 @@
                     j--;
                     i--;
                 } else {
-                    lastIndex = lastArr[text.charAt(i)] ? lastArr[text.charAt(i)] : -1;
+                    lastIndex = lastArr[text.charAt(i)] >= 0 ? lastArr[text.charAt(i)] : -1;
                     i += pLen - 1 - j + Math.max(j - lastIndex, matchArr[j]);
                     j = pLen - 1
                 }
@@ -62,21 +60,18 @@
                 }
             }
 
-            if (suffixArr[0] < pattern.length) {
-                for (let j = suffixArr[0] - 1; j >= 0; j--) {
-                    if (suffixArr[0] < matchArr[j]) {
-                        matchArr[j] = suffixArr[0]
-                    }
-                }
 
-                let j = suffixArr[0];
-                for (let k = suffixArr[j]; k < pattern.length; k = suffixArr[k]) {
-                    while (j < k) {
-                        if (matchArr[j] > k) {
-                            matchArr[j] = k
+            let k = 0;
+            while (k < pLen - 1) {
+                if (suffixArr[k] < pattern.length) {
+                    for (let j = suffixArr[k] - 1; j >= 0; j--) {
+                        if (suffixArr[k] < matchArr[j]) {
+                            matchArr[j] = suffixArr[k]
                         }
-                        j++
                     }
+                    break;
+                } else {
+                    k++
                 }
             }
         };
@@ -98,8 +93,7 @@
         match()
     }
 
-
-    BoyerMoore("HERE IS A SIMPLE LEAMPLE", "LEAMPLE")
+    BoyerMoore("here is a rxleple example", "example")
 </script>
 </body>
 </html>
