#include<iostream>
#include<stdio.h>
#include<conio.h>
#include<graphics.h>

using namespace std;

struct startu {
	int xstar;   //星星的X坐标
	int ystar;   //星星的Y坐标
	unsigned  radius;   //星星的半径
	int  pigment;  //星星的颜色
	int  margin;  //星星的间隔
};


struct startu   sttu[100];

void star(int i) {
	int ro = 0;

	sttu[i].xstar = rand() % 600;
	sttu[i].ystar = rand() % 400;
	sttu[i].radius = 1 + rand() % 3;
	sttu[i].margin = 1 + rand() % 5;
	ro = 255 * sttu[i].margin / 5;
	sttu[i].pigment = RGB(ro,ro,ro);


}


int main(void) {
	initgraph(600, 600);

	for(int i = 0; i < 100; i++) {
		star(i);
	}

	for (int i = 0; i < 100; i++) {
		setcolor(sttu[i].pigment);
		solidcircle(sttu[i].xstar,sttu[i].ystar,sttu[i].radius);
	}


	system("pause");
	return 0;
}

用c\c++实现的效果