Class Solution

LeetCode_problems/Compare Version Number/solution.cpp:15–59

class Solution {
public:
    int compareVersion(string version1, string version2) {
        string s = "", t = "";
        vector<int> v1,v2;
        
        for(char c: version1){
            if(c != '.'){
                s += c;                   // store each number substring from original string.
            }
            else{
                v1.push_back(stoi(s));    // if dot('.') convert string to number and append it to the vector, clear the string. 
                s = "";
            }
        }
        v1.push_back(stoi(s));            // for last set of number substring 
        
        for(char c: version2){
            if(c != '.'){
                t += c;
            }
            else{
                v2.push_back(stoi(t));
                t = "";
            }
        }
        v2.push_back(stoi(t));
        
        while(v1.size() < v2.size()){
            v1.push_back(0);                    // if size of v1 is less than v2 then append extra zeros(0) to v1
        }
        
        while(v2.size() < v1.size()){
            v2.push_back(0);                    // if size of v2 is less than v1 then append extra zeros(0) to v2
        }
        
        for(int i = 0; i < v1.size(); i++){     // compare the vector index wise
            if(v1[i] < v2[i])
                return -1;                      // if at any index, value of v1 is less than v2 return -1
            else if(v2[i] < v1[i])
                return 1;                       // if at any index, value of v2 is less than v1 return 1
        }
        return 0;                               // if all the values at all the indices are equal then return 0
    }
};