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
本题特殊情况要考虑到。v1 和v1.0 的比较。
public class Solution { public int compareVersion(String version1, String version2) { String[] splits1=version1.split("\.",-1); String[] splits2=version2.split("\.",-1); int shortLength=Math.min(splits1.length,splits2.length); int longLength=Math.max(splits2.length,splits1.length); int i=0; for(i=0;i<shortLength;i++) { if(Integer.parseInt(splits1[i])<Integer.parseInt(splits2[i])) { return -1; } else if(Integer.parseInt(splits1[i])>Integer.parseInt(splits2[i])) { return 1; } } if(i==longLength) { return 0; } else { while(i<longLength)//如果两个版本号不同长度,但是是同一版本的情况,如v1.0 和v1 { if(splits1.length==longLength) { if(Integer.parseInt(splits1[i])!=0) { return 1; } } else if(splits2.length==longLength) { if(Integer.parseInt(splits2[i])!=0) { return -1; } } i++; } return 0; } } }