[leetcode] CompareVersionNumbers

package temworkingarea;

import leetcode.tag.JavaEye;

@JavaEye
/**
* <pre>
* Compare two version numbers version1 and version1.
* If version1 > version2 return 1, if version1 < version2 return -1, otherwise return 0.
*
* You may assume that the version strings are non-empty and contain only digits and the . character.
* The . character does not represent a decimal point and is used to separate number sequences.
* For instance, 2.5 is not "two and a half" or "half way to version three", it is the fifth second-level revision of the second first-level revision.
*
*Here is an example of version numbers ordering:
*
*0.1 < 1.1 < 1.2 < 13.37
* </pre>
*/
public class CompareVersionNumbers {
    public class Solution {

        public int compareVersion(String version1, String version2) {

            long[] v_a = convert(version1);
            long[] v_b = convert(version2);
            v_a = convert(v_a, Math.max(v_a.length, v_b.length));
            v_b = convert(v_b, Math.max(v_a.length, v_b.length));

            for (int i = 0; i < Math.min(v_a.length, v_b.length); i++) {
                if (v_a[i] < v_b[i])
                    return -1;
                if (v_a[i] > v_b[i])
                    return 1;
            }
            return 0;
        }

        private long[] convert(String str) {
            String parts[] = str.split("\\.");
            long[] r = new long[parts.length];
            for (int i = 0; i < r.length; i++) {
                r[i] = Long.parseLong(parts[i]);
            }
            return r;
        }

        private long[] convert(long[] a, int length) {
            long[] r = new long[length];
            System.arraycopy(a, 0, r, 0, a.length);
            return r;
        }
    }
}