/*
for2.c : test program of "for" statements

$ cl.exe /O2 for2.c
$ for2.exe
*/

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <time.h>

int main(void)
{
	const int n = 2000;

	double *a = (double *)malloc(n * sizeof(double));
	double *b = (double *)malloc(n * sizeof(double));
	double *c = (double *)malloc(n * sizeof(double));
	double *d = (double *)malloc(n * sizeof(double));

	double **e = (double **)malloc(n * sizeof(double *));
	for (int i = 0; i < n; i++) {
		e[i] = (double *)malloc(n * sizeof(double));
	}

	srand(1);
	for (int i = 0; i < n; i++) {
		a[i] = rand() / RAND_MAX;
		b[i] = rand() / RAND_MAX;
		c[i] = rand() / RAND_MAX;
		d[i] = rand() / RAND_MAX;
	}

	// (1)
	clock_t t0 = clock();
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			e[i][j] = sin((a[i] - b[j]) * (c[i] + d[j]));
		}
	}

	// (2)
	clock_t t1 = clock();
	for (int j = 0; j < n; j++) {
		for (int i = 0; i < n; i++) {
			e[i][j] = sin((a[i] - b[j]) * (c[i] + d[j]));
		}
	}

	clock_t t2 = clock();
	printf("%d %.3f %.3f\n", n, (double)(t1 - t0) / CLOCKS_PER_SEC, (double)(t2 - t1) / CLOCKS_PER_SEC);

	return 0;
}