我正在读这个博客:-https://developerinsider.co/why-is-one-loop-so-Much-slower-than-two-loops/。我决定使用C++和Xcode来检验它。所以，我写了一个简单的程序，下面给出，当我执行它时，我对结果感到惊讶。实际上，第二个函数比第一个函数慢，这与文章中所说的相反。有谁能帮我弄清楚为什么会这样吗？

#include <iostream>
#include <vector>
#include <chrono>
    
using namespace std::chrono;
    
void function1() {
    const int n=100000;
            
    int a1[n], b1[n], c1[n], d1[n];
            
    for(int j=0;j<n;j++){
        a1[j] = 0;
        b1[j] = 0;
        c1[j] = 0;
        d1[j] = 0;
    }
            
    auto start = high_resolution_clock::now();
        
    for(int j=0;j<n;j++){
        a1[j] += b1[j];
        c1[j] += d1[j];
    }
            
    auto stop = high_resolution_clock::now();
    auto duration = duration_cast<microseconds>(stop - start);
        
    std::cout << duration.count() << " Microseconds." << std::endl;  
}
    
void function2() {
    const int n=100000;
            
    int a1[n], b1[n], c1[n], d1[n];
            
    for(int j=0; j<n; j++){
        a1[j] = 0;
        b1[j] = 0;
        c1[j] = 0;
        d1[j] = 0;
    }
            
    auto start = high_resolution_clock::now();
            
    for(int j=0; j<n; j++){
        a1[j] += b1[j];
    }
    
    for(int j=0;j<n;j++){
        c1[j] += d1[j];
    }
            
    auto stop = high_resolution_clock::now();
    auto duration = duration_cast<microseconds>(stop - start);
        
    std::cout << duration.count() << " Microseconds." << std::endl;
}
        
int main(int argc, const char * argv[]) {
    function1();
    function2();
    
    return 0;
}