Measuring execution time of a function in C++

Question

I want to find out how much time a certain function takes in my C++ program to execute on Linux. Afterwards, I want to make a speed comparison . I saw sever

Answer 1

Here's a function that will measure the execution time of any function passed as argument:

#include 
#include 

typedef std::chrono::high_resolution_clock::time_point TimeVar;

#define duration(a) std::chrono::duration_cast(a).count()
#define timeNow() std::chrono::high_resolution_clock::now()

template
double funcTime(F func, Args&&... args){
    TimeVar t1=timeNow();
    func(std::forward(args)...);
    return duration(timeNow()-t1);
}

Example usage:

#include 
#include 

typedef std::string String;

//first test function doing something
int countCharInString(String s, char delim){
    int count=0;
    String::size_type pos = s.find_first_of(delim);
    while ((pos = s.find_first_of(delim, pos)) != String::npos){
        count++;pos++;
    }
    return count;
}

//second test function doing the same thing in different way
int countWithAlgorithm(String s, char delim){
    return std::count(s.begin(),s.end(),delim);
}


int main(){
    std::cout<<"norm: "<

Output:

norm: 15555
algo: 2976