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;

}
};