LeetCode题解——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

Credits:

class Solution {public:    int compareVersion(string version1, string version2) {        int num1 = 0;        int num2 = 0;        int i=0, j=0;        int n1 = version1.size(), n2 = version2.size();        while(i<n1 || j<n2){            while(i<n1 && version1[i]!='.'){                num1= num1*10 + version1[i]-'0';                i++;            }                        while(j<n2 && version2[j]!='.'){                num2=num2*10 +version2[j]-'0';                j++;            }                        if(num1<num2) return -1;            if(num1>num2) return 1;                        num1 = 0;            num2 = 0;            i++;            j++;        }        return 0;            }};