Question

I need to create fibonacci's formula in C++ using a recursive and non-recursive formula. After doing so, I have to time each operation for for the following numbers of the sequence:

1, 5, 10, 15, 20, 25

I have to time how long the program took to perform each number recursive vs non recursive. Code in C++

Answer 1

#include <iostream>

using namespace std;

long FibRecurive(int n){

if(n==0)

return 1;

else if(n==1)

return 1;

else if(n==2)

return 2;

else

return FibRecurive(n-1) + FibRecurive(n-2);

}

long FibIterative(int n){

int a = 0, b = 1, c = 0;

for(int i=1; i<=n ; ++i){

c = a + b;

a = b;

b = c;

}

return c;

}

int main()

{

clock_t start, end;

start = clock();

for(int i=1; i<=5; ++i)

FibRecurive(i);

end = clock();

cout<<"Time Taken by Recurive for 5 element is "<<(end - start)/1000000.0<<endl;

start = clock();

for(int i=1; i<=5; ++i)

FibIterative(i);

end = clock();

cout<<"Time Taken by Iterative for 5 element is "<<(end - start)/1000000.0<<endl;

start = clock();

for(int i=1; i<=20; ++i)

FibRecurive(i);

end = clock();

cout<<"Time Taken by Recurive for 20 element is "<<(end - start)/1000000.0<<endl;

start = clock();

for(int i=1; i<=20; ++i)

FibIterative(i);

end = clock();

cout<<"Time Taken by Iterative for 20 element is "<<(end - start)/1000000.0<<endl;

return 0;

}

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SEE OUTPUT

PLEASE COMMENT if there is any concern.

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