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Java Solution for LeetCode algorithm problems, continually updating
package g0901_1000.s0906_super_palindromes;
// #Hard #Math #Enumeration #2022_03_28_Time_229_ms_(91.38%)_Space_42_MB_(93.10%)
public class Solution {
public int superpalindromesInRange(String left, String right) {
long l = Long.parseLong(left);
long r = Long.parseLong(right);
int cnt = 0;
long cur = 1;
while (true) {
long p1 = getPalindromeIncLastDigit(cur);
long p2 = getPalindromeExcLastDigit(cur);
long sq1 = p1 * p1;
long sq2 = p2 * p2;
if (sq2 > r) {
break;
}
if (sq1 >= l && sq1 <= r && isPalindrome(sq1)) {
cnt++;
}
if (sq2 >= l && isPalindrome(sq2)) {
cnt++;
}
cur++;
}
return cnt;
}
private boolean isPalindrome(long val) {
long construct = 0;
if (val % 10 == 0 && val >= 10) {
return false;
}
while (construct < val) {
construct = construct * 10 + val % 10;
val /= 10;
}
return construct == val || construct / 10 == val;
}
private long getPalindromeIncLastDigit(long val) {
long copy = val;
while (copy != 0) {
val = val * 10 + copy % 10;
copy /= 10;
}
return val;
}
private long getPalindromeExcLastDigit(long val) {
long copy = val / 10;
while (copy != 0) {
val = val * 10 + copy % 10;
copy /= 10;
}
return val;
}
}