palindrome

1function isPalindrome(sometext) {
2  var replace = /[.,'!?\- \"]/g; //regex for what chars to ignore when determining if palindrome
3  var text = sometext.replace(replace, '').toUpperCase(); //remove toUpperCase() for case-sensitive
4  for (var i = 0; i < Math.floor(text.length/2) - 1; i++) {
5    if(text.charAt(i) == text.charAt(text.length - 1 - i)) {
6      continue;
7    } else {
8      return false;
9    }
10  }
11  return true;
12}
13//EDIT: found this on https://medium.com/@jeanpan/javascript-splice-slice-split-745b1c1c05d2
14//, it is much more elegant:
15function isPalindrome(str) {
16  return str === str.split('').reverse().join(''); 
17}
18//you can still add the regex and toUpperCase() if you don't want case sensitive

1// devuelve cierto si la subcadena que hay entre las posiciones inicio y fin es palindromo.
2  bool esPalindromo(char cad[], int inicio, int fin){
3    bool pal = false;
4
5    if(inicio == fin){
6      pal = true;
7    }else{
8      if(cad[inicio] == cad[fin]){
9        pal = esPalindromo(cad, inicio + 1, fin - 1);
10      }
11    }
12
13    return pal;
14  }

1//made by Kashish Vaid the great.
2// Palindrome programme using for loop the easiest prgm
3#include <stdio.h>
4int main() {
5    int n, rev = 0, remainder, num;
6    printf("Enter an integer: ");
7    scanf("%d", &n);
8    num = n;
9
10    // reversed integer is stored in rev
11  for(num = n ; n!=0 ; n/=10)
12{
13    remainder = n%10;
14    rev = rev*10 + remainder;
15}
16// if else shortcuts
17    ( (rev == num) ? printf("%d is a palindrome.", num) : printf("%d is not a palindrome.", num) );
18    return 0;
19}
20//made by Kashish Vaid the great.

1#include<iostream>
2#include<string>
3#include<algorithm>
4bool IsPalindrome_true_false(const std::string& );
5
6int main ()
7{
8    
9    std::cout<<"Please enter a string:\t";
10    std::string str;
11    getline(std::cin, str);
12    
13    // convert the string from uppercase to lowercase 
14    int i = 0;
15    while(str[i])
16    {
17        if(str[i] == std::toupper(str[i]) && std::isalpha(str[i]) == 1024)
18        str[i]+= 32;
19        ++i;
20    }
21    // looping while string is empty 
22    while(str.empty())
23    {
24        std::cout<<"\nPlease enter a string your string is empty:\t";
25        if(!str.empty())
26        std::string str;
27        getline(std::cin, str);
28    }
29    
30    std::cout<<"\n"<<std::boolalpha<<IsPalindrome_true_false(str)<<std::endl;
31    std::cout<<std::endl;
32
33    return 0;
34}
35
36// check if string is a palindrome and return true or false 
37bool IsPalindrome_true_false(const std::string& str)
38{
39
40    int i = 0;                
41    int j = str.length() - 1; 
42
43    while(i <= j )
44    {   
45        
46        if(std::isalpha(str[i]) == 0){
47            ++i;
48            continue;
49        }else if(std::isalpha(str[j]) == 0){
50            --j;
51            continue;
52        }   
53        if(str[i] != str[j]){
54        
55           return false;
56        }
57        ++i;
58        --j;
59    }  
60    return true;
61}
62
63
64
65

1function isPalindrome(text) {
2  return [...text].reverse().join('') === text;
3}
4
5isPalindrome = text => {
6	return [...text].reverse().join('') === text;
7}
8
9isPalindrome = text => [...text].reverse().join('') === text;

1#include <stdio.h>
2int main() {
3    int n, reversedN = 0, remainder, originalN;
4    printf("Enter an integer: ");
5    scanf("%d", &n);
6    originalN = n;
7
8    // reversed integer is stored in reversedN
9    while (n != 0) {
10        remainder = n % 10;
11        reversedN = reversedN * 10 + remainder;
12        n /= 10;
13    }
14
15    // palindrome if orignalN and reversedN are equal
16    if (originalN == reversedN)
17        printf("%d is a palindrome.", originalN);
18    else
19        printf("%d is not a palindrome.", originalN);
20
21    return 0;
22}
23
24