Nuestro equipo especializado pasados ciertos días de trabajo y de recopilar de información, obtuvieron los datos necesarios, esperamos que resulte útil para ti para tu plan.
Ejemplo 1: ¿Cómo se detecta si una palabra es un palíndromo en javascript?
functionpalindrome(str)// Step 1. The first part is the same as earliervar re =/[^A-Za-z0-9]/g;// or var re = /[W_]/g;
str = str.toLowerCase().replace(re,'');// Step 2. Create the FOR loopvar len = str.length;// var len = "A man, a plan, a canal. Panama".length = 30for(var i =0; i < len/2; i++)if(str[i]!== str[len -1- i])// As long as the characters from each part match, the FOR loop will go onreturnfalse;// When the characters don't match anymore, false is returned and we exit the FOR loop/* Here len/2 = 15
For each iteration: i = ? i < len/2 i++ if(str[i] !== str[len - 1 - i])?
1st iteration: 0 yes 1 if(str[0] !== str[15 - 1 - 0])? => if("a" !== "a")? // false
2nd iteration: 1 yes 2 if(str[1] !== str[15 - 1 - 1])? => if("m" !== "m")? // false
3rd iteration: 2 yes 3 if(str[2] !== str[15 - 1 - 2])? => if("a" !== "a")? // false
4th iteration: 3 yes 4 if(str[3] !== str[15 - 1 - 3])? => if("n" !== "n")? // false
5th iteration: 4 yes 5 if(str[4] !== str[15 - 1 - 4])? => if("a" !== "a")? // false
6th iteration: 5 yes 6 if(str[5] !== str[15 - 1 - 5])? => if("p" !== "p")? // false
7th iteration: 6 yes 7 if(str[6] !== str[15 - 1 - 6])? => if("l" !== "l")? // false
8th iteration: 7 yes 8 if(str[7] !== str[15 - 1 - 7])? => if("a" !== "a")? // false
9th iteration: 8 yes 9 if(str[8] !== str[15 - 1 - 8])? => if("n" !== "n")? // false
10th iteration: 9 yes 10 if(str[9] !== str[15 - 1 - 9])? => if("a" !== "a")? // false
11th iteration: 10 yes 11 if(str[10] !== str[15 - 1 - 10])? => if("c" !== "c")? // false
12th iteration: 11 yes 12 if(str[11] !== str[15 - 1 - 11])? => if("a" !== "a")? // false
13th iteration: 12 yes 13 if(str[12] !== str[15 - 1 - 12])? => if("n" !== "n")? // false
14th iteration: 13 yes 14 if(str[13] !== str[15 - 1 - 13])? => if("a" !== "a")? // false
15th iteration: 14 yes 15 if(str[14] !== str[15 - 1 - 14])? => if("l" !== "l")? // false
16th iteration: 15 no
End of the FOR Loop*/returntrue;// Both parts are strictly equal, it returns true => The string is a palindromepalindrome("A man, a plan, a canal. Panama");
Ejemplo 2: ¿Cómo se detecta si una palabra es un palíndromo en javascript?
functionpalindrome(str)// Step 1. Lowercase the string and use the RegExp to remove unwanted characters from itvar re =/[W_]/g;// or var re = /[^A-Za-z0-9]/g;var lowRegStr = str.toLowerCase().replace(re,'');// str.toLowerCase() = "A man, a plan, a canal. Panama".toLowerCase() = "a man, a plan, a canal. panama"// str.replace(/[W_]/g, '') = "a man, a plan, a canal. panama".replace(/[W_]/g, '') = "amanaplanacanalpanama"// var lowRegStr = "amanaplanacanalpanama";// Step 2. Use the same chaining methods with built-in functions from the previous article 'Three Ways to Reverse a String in JavaScript'var reverseStr = lowRegStr.split('').reverse().join('');// lowRegStr.split('') = "amanaplanacanalpanama".split('') = ["a", "m", "a", "n", "a", "p", "l", "a", "n", "a", "c", "a", "n", "a", "l", "p", "a", "n", "a", "m", "a"]// ["a", "m", "a", "n", "a", "p", "l", "a", "n", "a", "c", "a", "n", "a", "l", "p", "a", "n", "a", "m", "a"].reverse() = ["a", "m", "a", "n", "a", "p", "l", "a", "n", "a", "c", "a", "n", "a", "l", "p", "a", "n", "a", "m", "a"]// ["a", "m", "a", "n", "a", "p", "l", "a", "n", "a", "c", "a", "n", "a", "l", "p", "a", "n", "a", "m", "a"].join('') = "amanaplanacanalpanama"// So, "amanaplanacanalpanama".split('').reverse().join('') = "amanaplanacanalpanama";// And, var reverseStr = "amanaplanacanalpanama";// Step 3. Check if reverseStr is strictly equals to lowRegStr and return a Booleanreturn reverseStr === lowRegStr;// "amanaplanacanalpanama" === "amanaplanacanalpanama"? => truepalindrome("A man, a plan, a canal. Panama");
Te mostramos las reseñas y valoraciones de los lectores
¡Haz clic para puntuar esta entrada!
(Votos: 0 Promedio: 0)