How do I store the reversed value (Palindrome Module 4 C++)

Question

My code:

#include <iostream>
using namespace std;

bool isPalindrome(int x) {
//complete the function
int n, reversedNumber, remainder;
x = reversedNumber;
while( n != 0) {
remainder = n%10;
reversedNumber = reversedNumber*10 + remainder;
n /= 10;
}
}

int main() {
int n;
cin >>n;

if(isPalindrome(n)) {
cout <<n<<" is a palindrome";
}
else {
cout << n<<" is NOT a palindrome";
}
return 0;
}

Would appreciate any help! :)

Answer 1

It should be

n = x;

and not

reversedNumber = x;

since the loop operates on 'n' as the copy of 'x', which is uninitialized right now. Everything else should be fine.

Answer 2

Plaush

You have to assign value of x to n but assigned it to reverseNumber so here your n is 0 that's why while (n != 0) will not work

Answer 3

Looks like you wanted to do
reversedNumber = x;
Instead of doing the exact opposite in the isPalindrome() function

Answer 4

Plaush You are not returning a value from the function based on the code in your question. Return the bool value of the test. See code below:

#include <iostream>
using namespace std;

bool isPalindrome(int x) {
//complete the function
int reversed, digit, num = x;

while (num>0) {
digit = num % 10;
reversed = reversed * 10 + digit;
num = num / 10;
}

return x == reversed;
}

int main() {
int n;
cin >>n;

if(isPalindrome(n)) {
cout <<n<<" is a palindrome";
}
else {
cout << n<<" is NOT a palindrome";
}
return 0;
}

Answer 5

Arsenic Tried that didn’t work. It just swap the ‘succesful and unsuccesful’ test around, if that makes any sense

E.G: My original code causes Test 1 to be correct but not test 2. Tried flipping x around, Test 2 is now correct but not Test 1

Edit: It didn’t swap, was probably seeing things, it still doesn’t work though :(

Answer 6

Plaush

In method return true if original number and reversed number are same otherwise return false.

Answer 7

Shadow Thank you so much! I can’t believe I didn’t know that :)

Answer 8

Tried Martin Taylor’s suggestion too, didn’t work.

Code:

#include <iostream>
using namespace std;

bool isPalindrome(int x) {
//complete the function
int n, reversedNumber = 0, remainder;
reversedNumber = x;
while( n != 0) {
remainder = n%10;
reversedNumber = reversedNumber*10 + remainder;
n /= 10;
}

if (reversedNumber==x){
return true;
}
else {
return false;
}

}

int main() {
int n;
cin >>n;

if(isPalindrome(n)) {
cout <<n<<" is a palindrome";
}
else {
cout << n<<" is NOT a palindrome";
}
return 0;
}

Edit: I know that there’s a simplier way but I wanna try the ‘given’ method :)