Determine if a string is a palindrome: use stack &reverse ()

first, the use of stacks

    functionStack () { This. DataStore = [];  This. top = 0;//the value of top is equal to the number of elements in the array         This. Push =push;  This. Pop =Pop; }    functionpush (Element) { This. datastore[ This. top++] =element; }    functionpop () {return  This. datastore[-- This. Top]; }    functionIspalindrome (word) {vars =NewStack ();//creates a new stack so that the elements in the array are pressed into the stack         for(vari = 0; i < word.length; ++i) {s.push (word[i]); }        varRWord = "";  while(S.top > 0) {RWord+ = S.pop ();//flips the elements in the new stack through the Pop () method        }        if(Word = =RWord) {            return true; } Else {            return false; }    }    varWord = "Hello"; if(Ispalindrome (Word)) {alert (Word+ "is a palindrome."); } Else{alert (Word+ "is not a palindrome."); } Word= "Racecar"; if(Ispalindrome (Word)) {alert (Word+ "is a palindrome."); } Else{alert (Word+ "is not a palindrome."); } 

second, indirect use of the reverse () method of the array

     functionIspalindrome (word) {varA = Word.split ("");//Convert the string to an array, split () "" is necessary        varb = A.join ();//Convert an array to a string        varA1 =A.reverse (); varB1 =A1.join (); if(b = = B1) {//string can use "= =", array can not            return true; } Else {            return false; }    }    varWord = "Hello"; if(Ispalindrome (Word)) {alert (Word+ "is a palindrome."); } Else{alert (Word+ "is not a palindrome."); } Word= "Racecar"; if(Ispalindrome (Word)) {alert (Word+ "is a palindrome."); } Else{alert (Word+ "is not a palindrome."); } 

Determine if a string is a palindrome: use stack &reverse ()