I want to make my code run. This is my code. How can I measure time elased for c
ID: 3729830 • Letter: I
Question
I want to make my code run.
This is my code.
How can I measure time elased for calculating Ackermann function?
If I run my code below, it always shows me 0 seconds. I think that is wrong.
I want to make code run by reducing // in //code_to_time();
What should I add to make this code run including code_to_time(); ???
Please help me..
----------------------------------------------------------------------------------------------------------------------------------------
#include <iostream> // cin, cout
#include <cmath> // For calculation.
#include <string> // string
#include <ctime>
using namespace std; // std::cout - > cout
// function prototype
double A(int, int); // The Ackermann function A(m,n)
void main()
{
int num1, num2; // number
cout << "Enter an two integer values ";
cout << " I will display the value of the Ackermann function" << endl;
cin >> num1 >> num2; // User will type numbers
clock_t begin, end;
begin = clock();
//code_to_time(); <<-- **** How can I make this code run to calculate how many times elapsed??
end = clock();
double elapsed_secs = (double(end - begin) / CLOCKS_PER_SEC);
// Try ... catch phrase
try
{
//Display the result
cout << "A(" << num1 << ", " << num2 << ")" << " answer is ";
cout << A(num1, num2) << " and it took " << elapsed_secs << " seconds." << endl;
}
catch (string exceptionString) // For the exception string
{
cout << exceptionString;
}
system("pause");
}
// Define A function
double A(int m, int n)
{
if (m == 0)
{ // If m = 0 return n + 1;
return n + 1;
}
if (m < 0 || n < 0)
{ // If m < 0 OR n < 0 throw an error.
string exceptionString = "Error ";
throw exceptionString;
}
if (n == 0)
{ // If n = 0 then return A(m-1, 1)
return A(m - 1, 1);
}
if (m > 0 && n > 0) // If m > 0 and n > 0 return A(m-1, A(m, n-1))
return A(m - 1, A(m, n - 1));
}
------------------------------------------------------------------------------------------------------------
Explanation / Answer
Hi,
i can see that there is no function call in the main() as a result the function is not getting executed and hence the time elapsed is 0
double A(int, int); // The Ackermann function A(m,n)
void main()
{
int num1, num2; // number
cout << "Enter an two integer values ";
cout << " I will display the value of the Ackermann function" << endl;
cin >> num1 >> num2; // User will type numbers
clock_t begin, end;
begin = clock();
//code_to_time(); <<-- **** How can I make this code run to calculate how many times elapsed??
// MAKE A FUNCTION CALL HERE like double A(int m, int n);
end = clock();
double elapsed_secs = (double(end - begin) / CLOCKS_PER_SEC);
// Try ... catch phrase
try
{
//Display the result
cout << "A(" << num1 << ", " << num2 << ")" << " answer is ";
cout << A(num1, num2) << " and it took " << elapsed_secs << " seconds." << endl;
}
catch (string exceptionString) // For the exception string
{
cout << exceptionString;
}
system("pause");
}
// Define A function
double A(int m, int n)
{
if (m == 0)
{ // If m = 0 return n + 1;
return n + 1;
}
if (m < 0 || n < 0)
{ // If m < 0 OR n < 0 throw an error.
string exceptionString = "Error ";
throw exceptionString;
}
if (n == 0)
{ // If n = 0 then return A(m-1, 1)
return A(m - 1, 1);
}
if (m > 0 && n > 0) // If m > 0 and n > 0 return A(m-1, A(m, n-1))
return A(m - 1, A(m, n - 1));
}
As I can see from your question, it looks like you want to know the elapsed time after execution of some piece of code. I guess it would be comfortable to see the results in second(s). If so, try using difftime() function as shown below. Hope this solves your problem
#include <time.h>
#include <stdio.h>
time_t start,end;
time (&start);
.
.
.
<your code>
.
.
.
time (&end);
double dif = difftime (end,start);
printf ("Elasped time is %.2lf seconds.", dif );
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.