Loop comparison, C++ (gcc)

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//Microsoft (R) C/C++ Optimizing Compiler Version 19.00.23506 for x86

#include <iostream>
#include <array>

#include <chrono>

int main()
{
  const int cIterations = 100000;
  
  // Classic loop 
  {      
    auto start = std::chrono::steady_clock::now();

std::cout << "Start...\n";
    int x = 0;
    int j = 0;
    for (auto i = 0; i < cIterations; ++i)
    {
      ++j;
      x += j;
    }
    std::cout << "...Done\n";
    std::cout << "x = " << x << "\n";
    auto end = std::chrono::steady_clock::now();
    std::cout << "Time for classic loop 1: " << std::chrono::duration <double, std::milli> (end - start).count() << "\n";
  }
    
  //  Range-based loop
  {
    auto start = std::chrono::steady_clock::now();

std::cout << "Start...";
    std::array<bool,cIterations> wArray;
    int x = 0;
    int j = 0;  
    for (auto wIt : wArray)
    {
      ++j;
      x += j;
    }
    std::cout << "...Done\n";
    std::cout << "x = " << x << "\n";
    auto end = std::chrono::steady_clock::now();
    std::cout << "Time for range-based loop 2: " << std::chrono::duration <double, std::milli> (end - start).count() << "\n";
  }
   
    
      // Classic loop 
  {      
    auto start = std::chrono::steady_clock::now();

std::cout << "Start...\n";
    int x = 0;
    int j = 0;
    for (auto i = 0; i < cIterations; ++i)
    {
      ++j;
      x += j;
    }
    std::cout << "...Done\n";
    std::cout << "x = " << x << "\n";
    auto end = std::chrono::steady_clock::now();
    std::cout << "Time for classic loop 3: " << std::chrono::duration <double, std::milli> (end - start).count() << "\n";
  }
    
  //  Range-based loop
  {
    auto start = std::chrono::steady_clock::now();

std::cout << "Start...";
    std::array<bool,cIterations> wArray;
    int x = 0;
    int j = 0;  
    for (auto wIt : wArray)
    {
      ++j;
      x += j;
    }
    std::cout << "...Done\n";
    std::cout << "x = " << x << "\n";
    auto end = std::chrono::steady_clock::now();
    std::cout << "Time for range-based loop 4: " << std::chrono::duration <double, std::milli> (end - start).count() << "\n";
  }
}

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Compilation time: 0.53 sec, absolute running time: 0.11 sec, cpu time: 0.02 sec, memory peak: 3 Mb, absolute service time: 0,65 sec