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@@ -0,0 +1,25 @@
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+/**
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+ * 判断一个整数是否是回文数。回文数是指正序（从左向右）和倒序（从右向左）读都是一样的整数。
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+ */
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+public class PalindromeNumber {
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+ public boolean isPalindrome(int x) {
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+ if (x < 0) return false;
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+ int length = 0;
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+ int y = x;
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+ while (y > 0) {
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+ y = y / 10;
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+ length++;
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+ }
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+
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+ for (int i = 0; i < length / 2; i++) {
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+ int end = x / (int) Math.pow(10, i) % 10;
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+ int start = x / (int) Math.pow(10, (length - i - 1)) % 10;
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+ if (start != end) return false;
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+ }
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+ return true;
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+ }
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+
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+ public static void main(String[] args) {
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+ System.out.println(new PalindromeNumber().isPalindrome(12));
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+ }
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+}
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