165 Compare Version Numbers

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

1、String类的使用

split方法,不能使用“.”进行分割,因为split实际使用了正则表达式,而“.”在正则里是特殊字符,故要使用“[.]”形式

 2、数据的考虑

不要认为输入数据都是X.X的形式,还有特殊的形式,如1.0和1、01和1,1和1.0等,因为这关系到这个算法里比较到什么时候结束,

3、感觉自己学的不错,而实际上依然是眼高手低,

4、算法的改进方面,希望各位大哥大姐能够提出宝贵意见

5、小小算法,在各位面前献丑了

public class Solution {
    public int compareVersion(String version1, String version2) {
        String[] ver1 = version1.split("[.]");
        String[] ver2 = version2.split("[.]");
        int[] v1 = new int[ver1.length];
        int[] v2 = new int[ver2.length];
        for(int i = 0 ; i < ver1.length; i ++){
            v1[i] = Integer.parseInt(ver1[i]);
        }
        for(int i = 0 ; i < ver2.length; i ++){
            v2[i] = Integer.parseInt(ver2[i]);
        }
        int i = 0 ;
        for(i = 0; i < v1.length && i < v2.length; i ++){
            if(v1[i] < v2[i]){
                return -1;
            }else if(v1[i] > v2[i]){
                return 1;
            }else if(v1[i] == v2[i]){
                continue;
            }
        }
        if(i < v1.length){//v1还有数据,
            if(v1[i] != 0)
                return 1;
        }
        if(i < v2.length){
            if(v2[i] != 0)
                return -1;
        }
        return 0;
    }
}

你可能感兴趣的:(LeetCode,version,compare,numb)