iterVSrec.cpp

// Autor: Bruno Furtado
// https://gist.github.com/brunofurmon

#include <iostream>
#include <fstream>

#include <sys/time.h>

// Método Recursivo
void potRec(int base, int exponent) {
	if (exponent == 0) {
		return; // result = 1
	}
	return potRec(base, exponent -1);
}

// Método Iterativo
void potIter(int base, int exponent) {
	int result = 1;
	for (int i = exponent; i > 0; i--) {
		result *= base;
	}
}


int main (int argc, char** argv) {
	timespec timeBegin;
	timespec timeEnd;
	const int mainBase = 3;
	const int maxExp = 1E4;
	const int minExp = 1E3;


	std::ofstream iterP;
	std::ofstream recP;

	iterP.open("ITER.csv");
	recP.open("REC.csv");

	for (int exp = minExp; exp < maxExp; exp++) {

		clock_gettime(CLOCK_REALTIME, &timeBegin);
		potIter(mainBase, exp);
		clock_gettime(CLOCK_REALTIME, &timeEnd);
		iterP << (timeEnd.tv_nsec - timeBegin.tv_nsec) << ", ";
		//std::cout << "Tempo ITER: " << timeEnd.tv_nsec - timeBegin.tv_nsec << "\n";

		clock_gettime(CLOCK_REALTIME, &timeBegin);
		potRec(mainBase, exp);
		clock_gettime(CLOCK_REALTIME, &timeEnd);
		recP << (timeEnd.tv_nsec - timeBegin.tv_nsec) << ", ";
		//std::cout << "Tempo REC: " << timeEnd.tv_nsec - timeBegin.tv_nsec << "\n";
	}
	
	iterP.close();
	recP.close();

	return 0;
}