每日一题：版本号比较

题目

给你两个版本号 version1 和 version2，请你比较它们。

版本号由一个或多个修订号组成，各修订号由一个 . 连接。每个修订号由多位数字组成，可能包含前导零。每个版本号至少包含一个字符。修订号从左到右编号，下标从 0 开始，最左边的修订号下标为 0，下一个修订号下标为 1，以此类推。例如，2.5.33 和 0.1 都是有效的版本号。

比较版本号时，请按从左到右的顺序依次比较它们的修订号。比较修订号时，只需比较忽略任何前导零后的整数值。也就是说，修订号 1 和修订号 001 相等。如果版本号没有指定某个下标处的修订号，则该修订号视为 0。例如，版本 1.0 小于版本 1.1，因为它们下标为 0 的修订号相同，而下标为 1 的修订号分别为 0 和 1，0 < 1。

返回规则如下：

• 如果 version1 > version2 返回 1，
• 如果 version1 < version2 返回 -1，
• 除此之外返回 0。

demo

#include <iostream>
#include <string>
#include <sstream>
#include <vector>
#include <algorithm>

// Helper function to split the version string into revision numbers
std::vector<int> splitVersion(const std::string& version) {
    std::vector<int> revisions;
    std::stringstream ss(version);
    std::string revision;
    
    while (std::getline(ss, revision, '.')) {
        // Remove leading zeros
        auto it = std::find_if(revision.rbegin(), revision.rend(), [](char c) { return c != '0'; });
        std::string number_str = (it == revision.rend()) ? "0" : std::string(revision.begin(), it.base());
        
        // Convert the remaining part (or "0" if all were zeros) to an integer
        revisions.push_back(std::stoi(number_str));
    }
    
    // If the versions have different number of revisions, pad with zeros
    while (revisions.size() < 4) { // Assuming a maximum of 4 revisions for simplicity, adjust as needed
        revisions.push_back(0);
    }
    
    // Trim trailing zeros (optional, depending on how you want to handle versions like "1.000")
    // This step is not strictly necessary for comparison as padding with zeros should make them equivalent
    // but can be useful for display purposes
    while (!revisions.empty() && revisions.back() == 0) {
        revisions.pop_back();
    }
    
    return revisions;
}

int solution(std::string version1, std::string version2) {
    std::vector<int> v1 = splitVersion(version1);
    std::vector<int> v2 = splitVersion(version2);
    
    // Ensure both versions have the same number of revisions by padding with zeros (already done in splitVersion)
    size_t max_length = std::max(v1.size(), v2.size());
    v1.resize(max_length, 0);
    v2.resize(max_length, 0);
    
    // Compare the versions
    for (size_t i = 0; i < max_length; ++i) {
        if (v1[i] > v2[i]) {
            return 1;
        } else if (v1[i] < v2[i]) {
            return -1;
        }
    }
    
    return 0;
}

int main() {
    std::cout << (solution("0.1", "1.1") == -1) << std::endl; // Should print 1 (true)
    std::cout << (solution("1.0.1", "1") == 1) << std::endl;  // Should print 1 (true), but note that "1" is equivalent to "1.0.0"
    std::cout << (solution("7.5.2.4", "7.5.3") == -1) << std::endl; // Should print 1 (true)
    std::cout << (solution("1.0", "1.0.0") == 0) << std::endl; // Should print 1 (true) because they are equal after padding

    return 0;
}