LeetCode-in-Java
2443. Sum of Number and Its Reverse
Medium
Given a non-negative integer num, return true if num can be expressed as the sum of any non-negative integer and its reverse, or false otherwise.
Example 1:
Input: num = 443
Output: true
Explanation: 172 + 271 = 443 so we return true.
Example 2:
Input: num = 63
Output: false
Explanation: 63 cannot be expressed as the sum of a non-negative integer and its reverse so we return false.
Example 3:
Input: num = 181
Output: true
Explanation: 140 + 041 = 181 so we return true. Note that when a number is reversed, there may be leading zeros.
Constraints:
0 <= num <= 105
Solution
public class Solution {
public boolean sumOfNumberAndReverse(int num) {
for (int i = 0; i <= num; ++i) {
int n = i;
int r = 0;
while (n != 0) {
r = r * 10 + n % 10;
n = n / 10;
}
if (r + i == num) {
return true;
}
}
return false;
}
}