Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression

/
/
gm

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)l4.1" Local $sString = "// Lab 4.1" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "#include <iostream>" & @CRLF & _ "#include <stdlib.h>" & @CRLF & _ "" & @CRLF & _ "using namespace std;" & @CRLF & _ "" & @CRLF & _ "int n, m;" & @CRLF & _ "int a[21], b[21], c[42];" & @CRLF & _ "" & @CRLF & _ "// Cau 1" & @CRLF & _ "void createArray() {" & @CRLF & _ " int i;" & @CRLF & _ "" & @CRLF & _ " do {" & @CRLF & _ " cout << " - Nhap gia tri cua n: ";" & @CRLF & _ " cin >> n;" & @CRLF & _ " } while (10 > n || n > 20);" & @CRLF & _ "" & @CRLF & _ " // Khoi tao 2 mang A & B co n phan tu" & @CRLF & _ " for (i = 0; i < n; i++) {" & @CRLF & _ " a[i] = rand() % 490 + 10;" & @CRLF & _ " b[i] = rand() % 490 + 10;" & @CRLF & _ " }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "void printArray(int *array, int len) {" & @CRLF & _ " int i;" & @CRLF & _ "" & @CRLF & _ " for (i = 0; i < len; i++) {" & @CRLF & _ " cout << "\t" << array[i];" & @CRLF & _ " }" & @CRLF & _ " cout << endl;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "void chanA_LeB() {" & @CRLF & _ " int i, j;" & @CRLF & _ " j = 0;" & @CRLF & _ " for (i = 0; i < n; i++) {" & @CRLF & _ " if (a[i] % 2 == 0) {" & @CRLF & _ " c[j] = a[i];" & @CRLF & _ " j++;" & @CRLF & _ " }" & @CRLF & _ " if (b[i] % 2 != 0) {" & @CRLF & _ " c[j] = b[i];" & @CRLF & _ " j++;" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ " m = j;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "int mul_is_safe(int a, int b) {" & @CRLF & _ " if (b > INT_MAX / a)" & @CRLF & _ " return 0;" & @CRLF & _ " return 1;" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "void mulArray() {" & @CRLF & _ " int i, j;" & @CRLF & _ " long long KQ;" & @CRLF & _ " KQ = 1;" & @CRLF & _ "" & @CRLF & _ " for (i = 0; i < m; i++) {" & @CRLF & _ " if (mul_is_safe(c[i], KQ)) {" & @CRLF & _ " cout << c[i];" & @CRLF & _ " KQ *= c[i];" & @CRLF & _ " for (j = i-1; j >= 0; j--) {" & @CRLF & _ " if (i != 0)" & @CRLF & _ " cout << " * " << c[j];" & @CRLF & _ " }" & @CRLF & _ " cout << " = " << KQ << endl;" & @CRLF & _ " }" & @CRLF & _ " else {" & @CRLF & _ " cout << "Integer Overflow" << endl << endl;" & @CRLF & _ " return;" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ "}" & @CRLF & _ "" & @CRLF & _ "int main() {" & @CRLF & _ "" & @CRLF & _ " // Cau 1" & @CRLF & _ " cout << "Cau 1: " << endl;" & @CRLF & _ " createArray();" & @CRLF & _ "" & @CRLF & _ " // Cau 2" & @CRLF & _ " cout << endl << "Cau 2: " << endl;" & @CRLF & _ " cout << " - Mang A: " << endl;" & @CRLF & _ " printArray(a, n);" & @CRLF & _ " cout << " - Mang B: " << endl;" & @CRLF & _ " printArray(b, n);" & @CRLF & _ "" & @CRLF & _ " // Cau 3" & @CRLF & _ " cout << endl << "Cau 3: " << endl;" & @CRLF & _ " chanA_LeB();" & @CRLF & _ " cout << " - Mang C: " << endl;" & @CRLF & _ " printArray(c, m);" & @CRLF & _ "" & @CRLF & _ " // Cau 4" & @CRLF & _ " cout << endl << "Cau 4: " << endl;" & @CRLF & _ " mulArray();" & @CRLF & _ "" & @CRLF & _ " //system("pause");" & @CRLF & _ " return 0;" & @CRLF & _ "}" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm