Compare Version Numbers

Compare two version numbers version1 and version2.
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

Runtime: 0ms

class Solution {
public:
int compareVersion(string version1, string version2) {
int m = version1.size(), n = version2.size();
int i = 0, j = 0;

while(i < m || j < n){
int temp1 = 0, temp2 = 0;
while(i < m && version1[i] != '.'){
temp1 = temp1 * 10 + version1[i] - '0';
i++;
}
while(j < n && version2[j] != '.'){
temp2 = temp2 * 10 + version2[j] - '0';
j++;
}
if(temp1 > temp2) return 1;
if(temp1 < temp2) return -1;
i++;
j++;
}
return 0;
}
};