markdown.go (view raw)
1//
2// Blackfriday Markdown Processor
3// Available at http://github.com/russross/blackfriday
4//
5// Copyright © 2011 Russ Ross <russ@russross.com>.
6// Distributed under the Simplified BSD License.
7// See README.md for details.
8//
9
10//
11//
12// Markdown parsing and processing
13//
14//
15
16// Blackfriday markdown processor.
17//
18// Translates plain text with simple formatting rules into HTML or LaTeX.
19package blackfriday
20
21import (
22 "bytes"
23 "unicode/utf8"
24)
25
26const VERSION = "1.1"
27
28// These are the supported markdown parsing extensions.
29// OR these values together to select multiple extensions.
30const (
31 EXTENSION_NO_INTRA_EMPHASIS = 1 << iota // ignore emphasis markers inside words
32 EXTENSION_TABLES // render tables
33 EXTENSION_FENCED_CODE // render fenced code blocks
34 EXTENSION_AUTOLINK // detect embedded URLs that are not explicitly marked
35 EXTENSION_STRIKETHROUGH // strikethrough text using ~~test~~
36 EXTENSION_LAX_HTML_BLOCKS // loosen up HTML block parsing rules
37 EXTENSION_SPACE_HEADERS // be strict about prefix header rules
38 EXTENSION_HARD_LINE_BREAK // translate newlines into line breaks
39 EXTENSION_TAB_SIZE_EIGHT // expand tabs to eight spaces instead of four
40 EXTENSION_FOOTNOTES // Pandoc-style footnotes
41 EXTENSION_NO_EMPTY_LINE_BEFORE_BLOCK // No need to insert an empty line to start a (code, quote, order list, unorder list)block
42)
43
44// These are the possible flag values for the link renderer.
45// Only a single one of these values will be used; they are not ORed together.
46// These are mostly of interest if you are writing a new output format.
47const (
48 LINK_TYPE_NOT_AUTOLINK = iota
49 LINK_TYPE_NORMAL
50 LINK_TYPE_EMAIL
51)
52
53// These are the possible flag values for the ListItem renderer.
54// Multiple flag values may be ORed together.
55// These are mostly of interest if you are writing a new output format.
56const (
57 LIST_TYPE_ORDERED = 1 << iota
58 LIST_ITEM_CONTAINS_BLOCK
59 LIST_ITEM_BEGINNING_OF_LIST
60 LIST_ITEM_END_OF_LIST
61)
62
63// These are the possible flag values for the table cell renderer.
64// Only a single one of these values will be used; they are not ORed together.
65// These are mostly of interest if you are writing a new output format.
66const (
67 TABLE_ALIGNMENT_LEFT = 1 << iota
68 TABLE_ALIGNMENT_RIGHT
69 TABLE_ALIGNMENT_CENTER = (TABLE_ALIGNMENT_LEFT | TABLE_ALIGNMENT_RIGHT)
70)
71
72// The size of a tab stop.
73const (
74 TAB_SIZE_DEFAULT = 4
75 TAB_SIZE_EIGHT = 8
76)
77
78// These are the tags that are recognized as HTML block tags.
79// Any of these can be included in markdown text without special escaping.
80var blockTags = map[string]bool{
81 "p": true,
82 "dl": true,
83 "h1": true,
84 "h2": true,
85 "h3": true,
86 "h4": true,
87 "h5": true,
88 "h6": true,
89 "ol": true,
90 "ul": true,
91 "del": true,
92 "div": true,
93 "ins": true,
94 "pre": true,
95 "form": true,
96 "math": true,
97 "table": true,
98 "iframe": true,
99 "script": true,
100 "fieldset": true,
101 "noscript": true,
102 "blockquote": true,
103
104 // HTML5
105 "video": true,
106 "aside": true,
107 "canvas": true,
108 "figure": true,
109 "footer": true,
110 "header": true,
111 "hgroup": true,
112 "output": true,
113 "article": true,
114 "section": true,
115 "progress": true,
116 "figcaption": true,
117}
118
119// Renderer is the rendering interface.
120// This is mostly of interest if you are implementing a new rendering format.
121//
122// When a byte slice is provided, it contains the (rendered) contents of the
123// element.
124//
125// When a callback is provided instead, it will write the contents of the
126// respective element directly to the output buffer and return true on success.
127// If the callback returns false, the rendering function should reset the
128// output buffer as though it had never been called.
129//
130// Currently Html and Latex implementations are provided
131type Renderer interface {
132 // block-level callbacks
133 BlockCode(out *bytes.Buffer, text []byte, lang string)
134 BlockQuote(out *bytes.Buffer, text []byte)
135 BlockHtml(out *bytes.Buffer, text []byte)
136 Header(out *bytes.Buffer, text func() bool, level int)
137 HRule(out *bytes.Buffer)
138 List(out *bytes.Buffer, text func() bool, flags int)
139 ListItem(out *bytes.Buffer, text []byte, flags int)
140 Paragraph(out *bytes.Buffer, text func() bool)
141 Table(out *bytes.Buffer, header []byte, body []byte, columnData []int)
142 TableRow(out *bytes.Buffer, text []byte)
143 TableHeaderCell(out *bytes.Buffer, text []byte, flags int)
144 TableCell(out *bytes.Buffer, text []byte, flags int)
145 Footnotes(out *bytes.Buffer, text func() bool)
146 FootnoteItem(out *bytes.Buffer, name, text []byte, flags int)
147
148 // Span-level callbacks
149 AutoLink(out *bytes.Buffer, link []byte, kind int)
150 CodeSpan(out *bytes.Buffer, text []byte)
151 DoubleEmphasis(out *bytes.Buffer, text []byte)
152 Emphasis(out *bytes.Buffer, text []byte)
153 Image(out *bytes.Buffer, link []byte, title []byte, alt []byte)
154 LineBreak(out *bytes.Buffer)
155 Link(out *bytes.Buffer, link []byte, title []byte, content []byte)
156 RawHtmlTag(out *bytes.Buffer, tag []byte)
157 TripleEmphasis(out *bytes.Buffer, text []byte)
158 StrikeThrough(out *bytes.Buffer, text []byte)
159 FootnoteRef(out *bytes.Buffer, ref []byte, id int)
160
161 // Low-level callbacks
162 Entity(out *bytes.Buffer, entity []byte)
163 NormalText(out *bytes.Buffer, text []byte)
164
165 // Header and footer
166 DocumentHeader(out *bytes.Buffer)
167 DocumentFooter(out *bytes.Buffer)
168
169 GetFlags() int
170}
171
172// Callback functions for inline parsing. One such function is defined
173// for each character that triggers a response when parsing inline data.
174type inlineParser func(p *parser, out *bytes.Buffer, data []byte, offset int) int
175
176// Parser holds runtime state used by the parser.
177// This is constructed by the Markdown function.
178type parser struct {
179 r Renderer
180 refs map[string]*reference
181 inlineCallback [256]inlineParser
182 flags int
183 nesting int
184 maxNesting int
185 insideLink bool
186
187 // Footnotes need to be ordered as well as available to quickly check for
188 // presence. If a ref is also a footnote, it's stored both in refs and here
189 // in notes. Slice is nil if footnotes not enabled.
190 notes []*reference
191}
192
193//
194//
195// Public interface
196//
197//
198
199// MarkdownBasic is a convenience function for simple rendering.
200// It processes markdown input with no extensions enabled.
201func MarkdownBasic(input []byte) []byte {
202 // set up the HTML renderer
203 htmlFlags := HTML_USE_XHTML
204 renderer := HtmlRenderer(htmlFlags, "", "")
205
206 // set up the parser
207 extensions := 0
208
209 return Markdown(input, renderer, extensions)
210}
211
212// Call Markdown with most useful extensions enabled
213// MarkdownCommon is a convenience function for simple rendering.
214// It processes markdown input with common extensions enabled, including:
215//
216// * Smartypants processing with smart fractions and LaTeX dashes
217//
218// * Intra-word emphasis suppression
219//
220// * Tables
221//
222// * Fenced code blocks
223//
224// * Autolinking
225//
226// * Strikethrough support
227//
228// * Strict header parsing
229func MarkdownCommon(input []byte) []byte {
230 // set up the HTML renderer
231 htmlFlags := 0
232 htmlFlags |= HTML_USE_XHTML
233 htmlFlags |= HTML_USE_SMARTYPANTS
234 htmlFlags |= HTML_SMARTYPANTS_FRACTIONS
235 htmlFlags |= HTML_SMARTYPANTS_LATEX_DASHES
236 htmlFlags |= HTML_SANITIZE_OUTPUT
237 renderer := HtmlRenderer(htmlFlags, "", "")
238
239 // set up the parser
240 extensions := 0
241 extensions |= EXTENSION_NO_INTRA_EMPHASIS
242 extensions |= EXTENSION_TABLES
243 extensions |= EXTENSION_FENCED_CODE
244 extensions |= EXTENSION_AUTOLINK
245 extensions |= EXTENSION_STRIKETHROUGH
246 extensions |= EXTENSION_SPACE_HEADERS
247
248 return Markdown(input, renderer, extensions)
249}
250
251// Markdown is the main rendering function.
252// It parses and renders a block of markdown-encoded text.
253// The supplied Renderer is used to format the output, and extensions dictates
254// which non-standard extensions are enabled.
255//
256// To use the supplied Html or LaTeX renderers, see HtmlRenderer and
257// LatexRenderer, respectively.
258func Markdown(input []byte, renderer Renderer, extensions int) []byte {
259 // no point in parsing if we can't render
260 if renderer == nil {
261 return nil
262 }
263
264 // fill in the render structure
265 p := new(parser)
266 p.r = renderer
267 p.flags = extensions
268 p.refs = make(map[string]*reference)
269 p.maxNesting = 16
270 p.insideLink = false
271
272 // register inline parsers
273 p.inlineCallback['*'] = emphasis
274 p.inlineCallback['_'] = emphasis
275 if extensions&EXTENSION_STRIKETHROUGH != 0 {
276 p.inlineCallback['~'] = emphasis
277 }
278 p.inlineCallback['`'] = codeSpan
279 p.inlineCallback['\n'] = lineBreak
280 p.inlineCallback['['] = link
281 p.inlineCallback['<'] = leftAngle
282 p.inlineCallback['\\'] = escape
283 p.inlineCallback['&'] = entity
284
285 if extensions&EXTENSION_AUTOLINK != 0 {
286 p.inlineCallback[':'] = autoLink
287 }
288
289 if extensions&EXTENSION_FOOTNOTES != 0 {
290 p.notes = make([]*reference, 0)
291 }
292
293 first := firstPass(p, input)
294 second := secondPass(p, first)
295
296 if renderer.GetFlags()&HTML_SANITIZE_OUTPUT != 0 {
297 second = sanitizeHtml(second)
298 }
299
300 return second
301}
302
303// first pass:
304// - extract references
305// - expand tabs
306// - normalize newlines
307// - copy everything else
308func firstPass(p *parser, input []byte) []byte {
309 var out bytes.Buffer
310 tabSize := TAB_SIZE_DEFAULT
311 if p.flags&EXTENSION_TAB_SIZE_EIGHT != 0 {
312 tabSize = TAB_SIZE_EIGHT
313 }
314 beg, end := 0, 0
315 for beg < len(input) { // iterate over lines
316 if end = isReference(p, input[beg:], tabSize); end > 0 {
317 beg += end
318 } else { // skip to the next line
319 end = beg
320 for end < len(input) && input[end] != '\n' && input[end] != '\r' {
321 end++
322 }
323
324 // add the line body if present
325 if end > beg {
326 expandTabs(&out, input[beg:end], tabSize)
327 }
328 out.WriteByte('\n')
329
330 if end < len(input) && input[end] == '\r' {
331 end++
332 }
333 if end < len(input) && input[end] == '\n' {
334 end++
335 }
336
337 beg = end
338 }
339 }
340
341 // empty input?
342 if out.Len() == 0 {
343 out.WriteByte('\n')
344 }
345
346 return out.Bytes()
347}
348
349// second pass: actual rendering
350func secondPass(p *parser, input []byte) []byte {
351 var output bytes.Buffer
352
353 p.r.DocumentHeader(&output)
354 p.block(&output, input)
355
356 if p.flags&EXTENSION_FOOTNOTES != 0 && len(p.notes) > 0 {
357 p.r.Footnotes(&output, func() bool {
358 flags := LIST_ITEM_BEGINNING_OF_LIST
359 for _, ref := range p.notes {
360 var buf bytes.Buffer
361 if ref.hasBlock {
362 flags |= LIST_ITEM_CONTAINS_BLOCK
363 p.block(&buf, ref.title)
364 } else {
365 p.inline(&buf, ref.title)
366 }
367 p.r.FootnoteItem(&output, ref.link, buf.Bytes(), flags)
368 flags &^= LIST_ITEM_BEGINNING_OF_LIST | LIST_ITEM_CONTAINS_BLOCK
369 }
370
371 return true
372 })
373 }
374
375 p.r.DocumentFooter(&output)
376
377 if p.nesting != 0 {
378 panic("Nesting level did not end at zero")
379 }
380
381 return output.Bytes()
382}
383
384//
385// Link references
386//
387// This section implements support for references that (usually) appear
388// as footnotes in a document, and can be referenced anywhere in the document.
389// The basic format is:
390//
391// [1]: http://www.google.com/ "Google"
392// [2]: http://www.github.com/ "Github"
393//
394// Anywhere in the document, the reference can be linked by referring to its
395// label, i.e., 1 and 2 in this example, as in:
396//
397// This library is hosted on [Github][2], a git hosting site.
398//
399// Actual footnotes as specified in Pandoc and supported by some other Markdown
400// libraries such as php-markdown are also taken care of. They look like this:
401//
402// This sentence needs a bit of further explanation.[^note]
403//
404// [^note]: This is the explanation.
405//
406// Footnotes should be placed at the end of the document in an ordered list.
407// Inline footnotes such as:
408//
409// Inline footnotes^[Not supported.] also exist.
410//
411// are not yet supported.
412
413// References are parsed and stored in this struct.
414type reference struct {
415 link []byte
416 title []byte
417 noteId int // 0 if not a footnote ref
418 hasBlock bool
419}
420
421// Check whether or not data starts with a reference link.
422// If so, it is parsed and stored in the list of references
423// (in the render struct).
424// Returns the number of bytes to skip to move past it,
425// or zero if the first line is not a reference.
426func isReference(p *parser, data []byte, tabSize int) int {
427 // up to 3 optional leading spaces
428 if len(data) < 4 {
429 return 0
430 }
431 i := 0
432 for i < 3 && data[i] == ' ' {
433 i++
434 }
435
436 noteId := 0
437
438 // id part: anything but a newline between brackets
439 if data[i] != '[' {
440 return 0
441 }
442 i++
443 if p.flags&EXTENSION_FOOTNOTES != 0 {
444 if data[i] == '^' {
445 // we can set it to anything here because the proper noteIds will
446 // be assigned later during the second pass. It just has to be != 0
447 noteId = 1
448 i++
449 }
450 }
451 idOffset := i
452 for i < len(data) && data[i] != '\n' && data[i] != '\r' && data[i] != ']' {
453 i++
454 }
455 if i >= len(data) || data[i] != ']' {
456 return 0
457 }
458 idEnd := i
459
460 // spacer: colon (space | tab)* newline? (space | tab)*
461 i++
462 if i >= len(data) || data[i] != ':' {
463 return 0
464 }
465 i++
466 for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
467 i++
468 }
469 if i < len(data) && (data[i] == '\n' || data[i] == '\r') {
470 i++
471 if i < len(data) && data[i] == '\n' && data[i-1] == '\r' {
472 i++
473 }
474 }
475 for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
476 i++
477 }
478 if i >= len(data) {
479 return 0
480 }
481
482 var (
483 linkOffset, linkEnd int
484 titleOffset, titleEnd int
485 lineEnd int
486 raw []byte
487 hasBlock bool
488 )
489
490 if p.flags&EXTENSION_FOOTNOTES != 0 && noteId != 0 {
491 linkOffset, linkEnd, raw, hasBlock = scanFootnote(p, data, i, tabSize)
492 lineEnd = linkEnd
493 } else {
494 linkOffset, linkEnd, titleOffset, titleEnd, lineEnd = scanLinkRef(p, data, i)
495 }
496 if lineEnd == 0 {
497 return 0
498 }
499
500 // a valid ref has been found
501
502 ref := &reference{
503 noteId: noteId,
504 hasBlock: hasBlock,
505 }
506
507 if noteId > 0 {
508 // reusing the link field for the id since footnotes don't have links
509 ref.link = data[idOffset:idEnd]
510 // if footnote, it's not really a title, it's the contained text
511 ref.title = raw
512 } else {
513 ref.link = data[linkOffset:linkEnd]
514 ref.title = data[titleOffset:titleEnd]
515 }
516
517 // id matches are case-insensitive
518 id := string(bytes.ToLower(data[idOffset:idEnd]))
519
520 p.refs[id] = ref
521
522 return lineEnd
523}
524
525func scanLinkRef(p *parser, data []byte, i int) (linkOffset, linkEnd, titleOffset, titleEnd, lineEnd int) {
526 // link: whitespace-free sequence, optionally between angle brackets
527 if data[i] == '<' {
528 i++
529 }
530 linkOffset = i
531 for i < len(data) && data[i] != ' ' && data[i] != '\t' && data[i] != '\n' && data[i] != '\r' {
532 i++
533 }
534 linkEnd = i
535 if data[linkOffset] == '<' && data[linkEnd-1] == '>' {
536 linkOffset++
537 linkEnd--
538 }
539
540 // optional spacer: (space | tab)* (newline | '\'' | '"' | '(' )
541 for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
542 i++
543 }
544 if i < len(data) && data[i] != '\n' && data[i] != '\r' && data[i] != '\'' && data[i] != '"' && data[i] != '(' {
545 return
546 }
547
548 // compute end-of-line
549 if i >= len(data) || data[i] == '\r' || data[i] == '\n' {
550 lineEnd = i
551 }
552 if i+1 < len(data) && data[i] == '\r' && data[i+1] == '\n' {
553 lineEnd++
554 }
555
556 // optional (space|tab)* spacer after a newline
557 if lineEnd > 0 {
558 i = lineEnd + 1
559 for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
560 i++
561 }
562 }
563
564 // optional title: any non-newline sequence enclosed in '"() alone on its line
565 if i+1 < len(data) && (data[i] == '\'' || data[i] == '"' || data[i] == '(') {
566 i++
567 titleOffset = i
568
569 // look for EOL
570 for i < len(data) && data[i] != '\n' && data[i] != '\r' {
571 i++
572 }
573 if i+1 < len(data) && data[i] == '\n' && data[i+1] == '\r' {
574 titleEnd = i + 1
575 } else {
576 titleEnd = i
577 }
578
579 // step back
580 i--
581 for i > titleOffset && (data[i] == ' ' || data[i] == '\t') {
582 i--
583 }
584 if i > titleOffset && (data[i] == '\'' || data[i] == '"' || data[i] == ')') {
585 lineEnd = titleEnd
586 titleEnd = i
587 }
588 }
589
590 return
591}
592
593// The first bit of this logic is the same as (*parser).listItem, but the rest
594// is much simpler. This function simply finds the entire block and shifts it
595// over by one tab if it is indeed a block (just returns the line if it's not).
596// blockEnd is the end of the section in the input buffer, and contents is the
597// extracted text that was shifted over one tab. It will need to be rendered at
598// the end of the document.
599func scanFootnote(p *parser, data []byte, i, indentSize int) (blockStart, blockEnd int, contents []byte, hasBlock bool) {
600 if i == 0 || len(data) == 0 {
601 return
602 }
603
604 // skip leading whitespace on first line
605 for i < len(data) && data[i] == ' ' {
606 i++
607 }
608
609 blockStart = i
610
611 // find the end of the line
612 blockEnd = i
613 for i < len(data) && data[i-1] != '\n' {
614 i++
615 }
616
617 // get working buffer
618 var raw bytes.Buffer
619
620 // put the first line into the working buffer
621 raw.Write(data[blockEnd:i])
622 blockEnd = i
623
624 // process the following lines
625 containsBlankLine := false
626
627gatherLines:
628 for blockEnd < len(data) {
629 i++
630
631 // find the end of this line
632 for i < len(data) && data[i-1] != '\n' {
633 i++
634 }
635
636 // if it is an empty line, guess that it is part of this item
637 // and move on to the next line
638 if p.isEmpty(data[blockEnd:i]) > 0 {
639 containsBlankLine = true
640 blockEnd = i
641 continue
642 }
643
644 n := 0
645 if n = isIndented(data[blockEnd:i], indentSize); n == 0 {
646 // this is the end of the block.
647 // we don't want to include this last line in the index.
648 break gatherLines
649 }
650
651 // if there were blank lines before this one, insert a new one now
652 if containsBlankLine {
653 raw.WriteByte('\n')
654 containsBlankLine = false
655 }
656
657 // get rid of that first tab, write to buffer
658 raw.Write(data[blockEnd+n : i])
659 hasBlock = true
660
661 blockEnd = i
662 }
663
664 if data[blockEnd-1] != '\n' {
665 raw.WriteByte('\n')
666 }
667
668 contents = raw.Bytes()
669
670 return
671}
672
673//
674//
675// Miscellaneous helper functions
676//
677//
678
679// Test if a character is a punctuation symbol.
680// Taken from a private function in regexp in the stdlib.
681func ispunct(c byte) bool {
682 for _, r := range []byte("!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~") {
683 if c == r {
684 return true
685 }
686 }
687 return false
688}
689
690// Test if a character is a whitespace character.
691func isspace(c byte) bool {
692 return c == ' ' || c == '\t' || c == '\n' || c == '\r' || c == '\f' || c == '\v'
693}
694
695// Test if a character is letter.
696func isletter(c byte) bool {
697 return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')
698}
699
700// Test if a character is a letter or a digit.
701// TODO: check when this is looking for ASCII alnum and when it should use unicode
702func isalnum(c byte) bool {
703 return (c >= '0' && c <= '9') || isletter(c)
704}
705
706// Replace tab characters with spaces, aligning to the next TAB_SIZE column.
707// always ends output with a newline
708func expandTabs(out *bytes.Buffer, line []byte, tabSize int) {
709 // first, check for common cases: no tabs, or only tabs at beginning of line
710 i, prefix := 0, 0
711 slowcase := false
712 for i = 0; i < len(line); i++ {
713 if line[i] == '\t' {
714 if prefix == i {
715 prefix++
716 } else {
717 slowcase = true
718 break
719 }
720 }
721 }
722
723 // no need to decode runes if all tabs are at the beginning of the line
724 if !slowcase {
725 for i = 0; i < prefix*tabSize; i++ {
726 out.WriteByte(' ')
727 }
728 out.Write(line[prefix:])
729 return
730 }
731
732 // the slow case: we need to count runes to figure out how
733 // many spaces to insert for each tab
734 column := 0
735 i = 0
736 for i < len(line) {
737 start := i
738 for i < len(line) && line[i] != '\t' {
739 _, size := utf8.DecodeRune(line[i:])
740 i += size
741 column++
742 }
743
744 if i > start {
745 out.Write(line[start:i])
746 }
747
748 if i >= len(line) {
749 break
750 }
751
752 for {
753 out.WriteByte(' ')
754 column++
755 if column%tabSize == 0 {
756 break
757 }
758 }
759
760 i++
761 }
762}
763
764// Find if a line counts as indented or not.
765// Returns number of characters the indent is (0 = not indented).
766func isIndented(data []byte, indentSize int) int {
767 if len(data) == 0 {
768 return 0
769 }
770 if data[0] == '\t' {
771 return 1
772 }
773 if len(data) < indentSize {
774 return 0
775 }
776 for i := 0; i < indentSize; i++ {
777 if data[i] != ' ' {
778 return 0
779 }
780 }
781 return indentSize
782}
783
784// Create a url-safe slug for fragments
785func slugify(in []byte) []byte {
786 if len(in) == 0 {
787 return in
788 }
789 out := make([]byte, 0, len(in))
790 sym := false
791
792 for _, ch := range in {
793 if isalnum(ch) {
794 sym = false
795 out = append(out, ch)
796 } else if sym {
797 continue
798 } else {
799 out = append(out, '-')
800 sym = true
801 }
802 }
803 var a, b int
804 var ch byte
805 for a, ch = range out {
806 if ch != '-' {
807 break
808 }
809 }
810 for b = len(out) - 1; b > 0; b-- {
811 if out[b] != '-' {
812 break
813 }
814 }
815 return out[a : b+1]
816}