Generate by random a set of n points in 2D Cartesian Coordinates System

[375jz8AR]

I have a problem with this code, when i try to run it the result is a lot of 0.00000. I need to generate random set of 2d points. I am new, so maybe what i wrote has no sense. Can someone help me?
#include <stdio.h>
#include <math.h>
#include <string.h>
#include<time.h>
#include <stdlib.h>
void main()
{
srand((unsigned)time(NULL));

int x[] = { rand() % 10 + 0 / (double)RAND_MAX + 0};
int y[] = { rand() % 10 + 0 / (double)RAND_MAX + 0};
for (double n = 0; n < 10; n++)
{

printf("%lf\n", x, y);

}
}

[anup30]

#include <iostream>
#include <ctime>
#include <cstdlib>
using namespace std;

int main ()
{
	srand(time(NULL));
	
	int x, y;
	bool xsign, ysign; // true if negative
	
	int arrX[5];
	int arrY[5];
	
	for(int i=0; i<5; i++)
	{
		x = rand()%100;
		y = rand()%100;
		xsign = rand()%2;
		ysign = rand()%2;
		
		if(xsign) x *= -1;
		if(ysign) y *= -1;
		
		arrX[i] = x;
		arrY[i] = y;		
	}	
	
	for (int i=0;i<5; i++) 	
		cout << arrX[i] << ", " << arrY[i] << endl;
	
	
return 0;	
} 

[375jz8AR]

Thank you very much, but can you explain me what did you do in
: if(xsign) x *= -1;
if(ysign) y *= -1;
thank you

[deathslice]

It's very simple. If xsign or ysign is true by random chance(really pseudo chance), you turn the coordinate(whether it's x or y) to a negative. You also don't want to modify the number so you simply multiply it by 1.

[anup30]

converts positive to negative.

[375jz8AR]

thank you, how can i put this expresion into printf(...), because i try, but it gives me big values.
cout << arrX[i] << ", " << arrY[i] << endl;

[deathslice]

Can you show us how you tried to implement it? In other words, show your code so then maybe we can see where you went wrong.

[375jz8AR]

in this case i only have one column of points.
#include <iostream>
#include <ctime>
#include <cstdlib>
using namespace std;

int main()
{
srand(time(NULL));

int x, y;
bool xsign, ysign; // true if negative

int arrX[5];
int arrY[5];

for (int i = 0; i<5; i++)
{
x = rand() % 100;
y = rand() % 100;
xsign = rand() % 2;
ysign = rand() % 2;

if (xsign) x *= -1;
if (ysign) y *= -1;

arrX[i] = x;
arrY[i] = y;
}

for (int i = 0; i < 5; i++)
printf("%d\n", arrX[i],arrY[i]);



return 0;

[deathslice]

Since you're outputting two coordinates, you need two arguments in your printf function. In this case, two %d %d. The 3 is to set the width of the output to make it look neat.

#include <iostream>
#include <ctime>
#include <cstdlib>
using namespace std;

int main()
{
srand(time(NULL));

int x, y;
bool xsign, ysign; // true if negative

int arrX[5];
int arrY[5];

for (int i = 0; i<5; i++)
{
x = rand() % 100;
y = rand() % 100;
xsign = rand() % 2;
ysign = rand() % 2;

if (xsign) x *= -1;
if (ysign) y *= -1;

arrX[i] = x;
arrY[i] = y;
}

for (int i = 0; i < 5; i++)
printf("%3d %3d\n", arrX[i],arrY[i]);



return 0;
}

[375jz8AR]

Thank you very much guys, you are great!!