catelog.cpp

#include <iostream>
#include <vector>
#include <string> 
#include <map>


struct Catelog {
  
    std::string region_name;
    int version;
    int dbytes;
    
    Catelog(const std::string r, const int v, const int d) {
        region_name = r;
        version = v;
        dbytes = d;
    }
};

using CatelogMap = std::map<int, Catelog>;


std::vector<std::string> break_string(const std::string &str, const std::string &deliminator) {
    std::vector<std::string> strings;

    std::string::size_type pos = 0;
    std::string::size_type prev = 0;
    while ((pos = str.find(deliminator, prev)) != std::string::npos) {
        auto x = str.substr(prev, pos - prev);
        if (!x.empty()) {
            strings.push_back(x);
        }
        prev = pos + 1;
    }
    
    auto x = str.substr(prev);
    if (!x.empty()) {
        strings.push_back(x);
    }
    return strings;
}   


CatelogMap build_catelogs(const std::string &str) {
    CatelogMap catelogs;
    auto strings = break_string(str, "\n");

    for (auto c_str: strings) {
        auto x = break_string(c_str, ",");
        std::string r = x[0];
        auto v = std::atoi(x[1].c_str());
        auto d = std::atoi(x[2].c_str());
        catelogs.insert({v, Catelog(r, v, d)});
    }
    return catelogs;    
}

int deserialize(const std::string &str, const std::string &t, const std::string &u) {
    
    auto installs = break_string(t, ",");
    int installed_version = std::atoi(installs[1].c_str());
    std::string installed_region = installs[0];
    
    auto catelogs = build_catelogs(str);

    int max_version = -1;
    for (auto it = catelogs.begin(); it != catelogs.end(); it++) {
        max_version = it->second.region_name == u ? std::max(it->first, max_version) : max_version;
    }
    
    if (max_version == -1) {
        return -1;
    }
    
    int total_download = 0;
    for (int i = installed_version + 1; i < max_version + 1; i++) {
        auto it = catelogs.find(i);
        if (it != catelogs.end()) {
            total_download += it->second.dbytes;
        }
    }
   return total_download;
}


int main() {
    
    
   std::string s = "Fiji,1,25000\n,Fiji,2,3000\n,Fiji,3,1000";
   std::string t = "Fiji,1";
   std::string u = "Fiji";
  
   int output = -1;
   output = deserialize(s, t, u);
   std::cout << "Output: " << output << "\n";
        
   s = "Fiji,1,25000\n,Fiji,2,3000\n,Fiji,3,1000";
   t = "Fiji,1";
   u = "India";
    
   output = deserialize(s, t, u);
   std::cout << "Output: " << output << "\n";
    
   s = "Fiji,1,25000\n,Fiji,2,3000\n,Fiji,3,1000";
   t = "Fiji,0";
   u = "Fiji";
    
   output = deserialize(s, t, u);
   std::cout << "Output: " << output << "\n";
    
}