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JS Recursive function (Fibonaccine sequence)

Instance resolution:

A set of numbers: 0 1 1 2 3 5 8 13 0 1 2 3 4 5 6 7 sl (0) = 0; sl (1) = 1; sl (2) = sl (0) + sl (1); sl (3) = sl (1) + sl (2); function sl (I) {if (iTunes 0) {return 0;} else if (iTunes 1) {return 1;} else {return sl (irel 1) + sl (irel 2) }}

Regular expression test

/ / verify whether it is composed entirely of numbers function isDigit (s) {var patrn=/ ^ [0-9] {1 patrn.exec 20} $/; if (! patrn.exec (s)) login} / / verify login name: only 5-20 logins can be entered, starting with a letter, with numbers, "_", "." The string function isRegisterUserName (s) {var patrn=/ ^ [a-zA-Z] {1} ([a-zA-Z0-9] | [. _]) {4 var patrn=/ 19} $/; if (! patrn.exec (s)) return falsereturn true} / / verify the user name: only 1-30 letters can be entered for function isTrueName (s) {var patrn=/ ^ [a-zA-Z] {1pm 30} $/ If (! patrn.exec (s)) return falsereturn true} / / check password: you can only enter 6-20 letters, numbers, and underscores function isPasswd (s) {var patrn=/ ^ (\ w) {6pm 20} $/ If (! patrn.exec (s)) return falsereturn true} / / verify ordinary telephone and fax numbers: you can start with "+" and contain "-" function isTel (s) {/ / var patrn=/ ^ [+] {0Mague 1} (\ d) {1Mague 3} []? ([-]? (\ d) {1cot 12}) + $/ Var patrn=/ ^ [+] {0jue 1} (\ d) {1JI 3} []? ([-]? ((\ d) | []) {1Jet 12}) + $/ If (! patrn.exec (s)) return falsereturn true} / / verify the mobile phone number: it must start with a number and may contain "-" function isMobil (s) {var patrn=/ ^ [+] {0jue 1} (\ d) {1prit 3} []? ([-]? (\ d) | []) {1m 12}) + $/ If (! patrn.exec (s)) return falsereturn true} / / check Postal Code function isPostalCode (s) {/ / var patrn=/ ^ [a-zA-Z0-9] {3 a-zA-Z0 12} $/; var patrn=/ ^ [a-zA-Z0-9] {3 a-zA-Z0 12} $/; if (! patrn.exec (s)) return falsereturn true} / / verify the search keyword function isSearch (s) {var patrn=/ ^ [^ `~! @ # $% ^ & * () + = |\\] [\]\ {\}: \'\,. /?] {1} [^ `~! @ $% ^ & () + = |\\] [\]\]\ {\}:;\'\,.] {0return falsereturn true 19} $/; if (! patrn.exec (s)) return falsereturn true} function isIP (s) / / by zergling {var patrn=/ ^ [0-9.] {1pm 20} $/ If (! patrn.exec (s)) return falsereturn true} * FUNCTION: isBetween* PARAMETERS: val AS any value* lo AS Lower limit to check* hi AS Higher limit to check* CALLS: NOTHING* RETURNS: TRUE if val is between lo and hi both inclusive, otherwise false.function isBetween (val, lo, hi) {if ((val)

< lo) || (val >

Hi) {return (false);} else {return (true);}} * FUNCTION: isDate checks a valid date* PARAMETERS: theStr AS String* CALLS: isBetween, isInt* RETURNS: TRUE if theStr is a valid date otherwise false.function isDate (theStr) {var the1st = theStr.indexOf ('-'); var the2nd = theStr.lastIndexOf ('-'); if (the1st = = the2nd) {return (false);} else {var y = theStr.substring (0mert the1st); var m = theStr.substring (the1st+1,the2nd) Var d = theStr.substring (the2nd+1,theStr.length); var maxDays = 31 false if (isInt (m) = = false | | isInt (d) = = false | | isInt (y) = = false) {return (false);} else if (y.length)

< 4) { return(false); }else if (!isBetween (m, 1, 12)) { return(false); }else if (m==4 || m==6 || m==9 || m==11) maxDays = 30;else if (m==2) {if (y % 4 >

0) maxDays = 28 return if (y% 100 = = 0 & & y% 400 > 0) maxDays = 28 return maxDays = 29;} if (isBetween (d, 1, maxDays) = = false) {return (false);} else {return (true);} * FUNCTION: isEuDate checks a valid date in British format* PARAMETERS: theStr AS String* CALLS: isBetween, isInt* RETURNS: TRUE if theStr is a valid date otherwise false.function isEuDate (theStr) {if (isBetween (theStr.length, 8,10) = false) {return (false) } else {var the1st = theStr.indexOf ('/'); var the2nd = theStr.lastIndexOf ('/'); if (the1st = = the2nd) {return (false);} else {var m = theStr.substring (the1st+1,the2nd); var d = theStr.substring; var y = theStr.substring (the2nd+1,theStr.length); var maxDays = 31 if (isInt (m) = false | isInt (d) = false | | isInt (y) = = false) {return (false);} else if (y.length)

< 4) { return(false); }else if (isBetween (m, 1, 12) == false) { return(false); }else if (m==4 || m==6 || m==9 || m==11) maxDays = 30;else if (m==2) {if (y % 4 >

0) maxDays = 28 return if (y% 100 = = 0 & & y% 400 > 0) maxDays = 28 * else maxDays = 29;} if (isBetween (d, 1, maxDays) = = false) {return (false);} else {return (true);} * FUNCTION: Compare Date! Which is the latestwaters * PARAMETERS: lessDate,moreDate AS String* CALLS: isDate,isBetween* RETURNS: TRUE if lessDateDate2) {return (false);} return (true);} * FUNCTION isEmpty checks if the parameter is empty or null* PARAMETER str AS Stringfunction isEmpty (str) {if ((str==null) | | (str.length==0)) return true;else return (false);} * FUNCTION: isInt* PARAMETER: theStr AS String* RETURNS: TRUE if the passed parameter is an integer, otherwise FALSE* CALLS: isDigitfunction isInt (theStr) {var flag = true If (isEmpty (theStr)) {flag=false;} else {for (var iTuno; I decLen) return (false); else if (! isInt (intPart) | |! isInt (decPart)) return (false); else if (isEmpty (decPart)) return (false); else return (true);} * FUNCTION: isEmail* PARAMETER: String (Email Address) * RETURNS: TRUE if the String is a valid Email address* FALSE if the passed string is not a valid Email Address* EMAIL FORMAT: AnyName@EmailServer e.g Webmaster@hotmail.com* @ sign can appear only once in the email address.function isEmail (theStr) {var atIndex = theStr.indexOf ('@'); var dotIndex = theStr.indexOf ('.', atIndex); var flag = true;theSub = theStr.substring (0, dotIndex+1) if ((atIndex)

< 1)||(atIndex != theStr.lastIndexOf('@'))||(dotIndex < atIndex + 2)||(theStr.length Document to open in the new windowhite ->

Height of the new windowwide-> Width of the new windowbars-> 1-Scroll bars= YES 0-Scroll Bars = NOresize-> 1-Resizable = YES 0-Resizable = NO* CALLS: NONE* RETURNS: New window instancefunction newWindow (doc, hite, wide, bars, resize) {var winNew= "_ blank"; var opt= "toolbar=0,location=0,directories=0,status=0,menubar=0,"; opt+= ("scrollbars=" + bars+ ","); opt+= ("resizable=" + resize+ ","); opt+= ("width=" + wide+ ","); opt+= ("height=" + hite) WinHandle=window.open (doc,winNew,opt); return;} * FUNCTION: DecimalFormat* PARAMETERS: paramValue-> Field value* CALLS: NONE* RETURNS: Formated stringfunction DecimalFormat (paramValue) {var intPart = parseInt (paramValue); var decPart = parseFloat (paramValue)-intPart;str = ""; if ((decPart = = 0) | (decPart = = null) str + = (intPart + ".00"); else str + = (intPart + decPart); return (str);}

Regular expression application

"^\\ integer $" / / non-negative integer (positive integer + 0) "^ [0-9] * [1-9] [0-9] * $" / / positive integer "^ (-\\ d+) | (0 +) $" / / non-positive integer (negative integer + 0) "^-[0-9] * $" / / negative integer "^ -? "/ / Integer" ^\ d+ (\.\ d+)? $"/ / non-negative floating point (positive floating point + 0)" ^ (([09] +. [09] * [1-9] [09] *) | ([09] * [1-9] [09] *. [09] +) | (0-9) * [1-9] [0-9] 9] *)) $"/ / positive floating point number" ^ ((-\\ d + (\\.\\ d+)?) | (0 + (\\ .0 +) $"/ / non-positive floating point number (negative floating point number + 0)" ^ (- ((0-9) +\. [0-9] * [1-9] [0-9] *) | ([0-9] * [0-9] * *) . [0-9] +) | ([0-9] * [1-9] [0-9] *)) $"/ / negative floating point number" ^ (-?\\ d +) (\\.\\ d +)? $"/ floating point number" ^ [A-Za-z] + $"/ 26-letter string" ^ [color AZ] + $"/ 26 letters large Write the string "^ [amurz] + $" / / the string "^ [A-Za-z0-9] + $" / / the string of numbers and 26 letters "^\\ wish$" / / consisting of numbers, The 26-letter or underlined string "^ [\\ w -] + (\\ .[\\ w -] +) * @ [\\ w -] + (\\ .[\\ w -] +) + $" / / email address "^ [a-zA-z] +: / / (\\ w+ (-\\ w+) *) (\. (\\ w+ (-\\ w+) *)) * (\\?\\ S*)? $" / url

Application of recursive function

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