text: #ifndef SYSTEM_H
  #define SYSTEM_H
  
  #include <string>
  #include <vector>
  
  #include "process.h"
  #include "processor.h"
  
  class System {
   public:
    Processor& Cpu();                   // TODO: See src/system.cpp
    std::vector<Process>& Processes();  // TODO: See src/system.cpp
    float MemoryUtilization();          // DONE: See src/system.cpp
    long UpTime();                      // DONE: See src/system.cpp
    int TotalProcesses();               // DONE: See src/system.cpp
    int RunningProcesses();             // DONE: See src/system.cpp
    std::string Kernel();               // DONE: See src/system.cpp
    std::string OperatingSystem();      // DONE: See src/system.cpp
  
    // TODO: Define any necessary private members
   private:
    std::string kernel_{};
    long uptime_{0};
    processes_{0};
  
    Processor cpu_ = {};
    std::vector<Process> processes_ = {};
    running_processes{0};
  
    enum MemType : int {
      kMemTotal_ = 0,
      kMemFree_,
      kBuffers_,
      kCached_,
      kShmem_,
      kSReclaimable_,
    };
  };
  
  #endif