* regex quick to remove unwanted characters\n* toLowerCase method can convert entire string one time\n* rest operator can convert string to an array, so that we can use array methods\n* every Array method is efficient by failing early\n* parameters for every method (elment of the array, index, source array)\n* We can introduce additional parameter to find out length of the string\n\n```var isPalindrome = function(s) {\n    return [...s.replace(/[^0-9a-zA-Z]+/g,"")\n\t\t\t\t\t.toLowerCase()]\n\t\t\t\t\t.every((c, i, src, l=src.length) => c === src[l-i-1]);\n};```

regex quick to remove unwanted characters\n toLowerCase method can convert entire string one time\n rest operator can convert string to an array, so that we can