Problem
Determine whether an integer is a palindrome. Do this without extra space.
My Solution
public class Solution {
int[] numbers = new int[20];
public boolean isPalindrome(int x) {
if (x >= 0) {
if (reverse(x) == x) {
return true;
}
}
return false;
}
public int reverse(int x) {
int i = 0, rX = 0, count = 0;
for (i = 0; x != 0; i++) {
numbers[i] = x % 10;
x /= 10;
}
count = i;
for (i = 0; i < count; i++) {
rX = rX * 10 + numbers[i];
}
return rX;
}
}
Great Solution
public boolean isPalindrome(int x) {
if(x<0 || (x!=0 && x%10==0))
return false;
int res = 0;
while(x>res){
res = res*10 + x%10;
x = x/10;
}
return (x==res || x==res/10);
}
