Question

Please help with C

Thanks

Declare a structure to represent a circle. Each circle stores information about the center and the radius. Center is represented with x and y coordinates. Both center and radius uses doubles. Allocate an array of 50 circle pointers and dynamically allocate memory to store a circle pointed by cash array eatery. Randomly generate circles using the following function. double rand_float (double a.double b) {return ((double)rand()/RAND_MAX)=(b-a)+a:} We want all the circles to fit an area of 1000 times 1000. So, x and y coordinates are randomly selected from (100, 900) and radius is randomly selected from (0, 100) using above function. After you insert the random circles, find the circle with the largest area and print the information for this circle. You can use 3.14 for PI and area of a circle is given as PI = radius = radius. Don't forget to free the pointers when you are done with the array. Use Valerian to find any memory leaks. Sample execution is given below

Answer 1

// C code
#include <stdio.h>
#include <stdlib.h>
#define PI 3.14

typedef struct circle
{
double x;
double y;
double radius;
} Circle;

double rand_float(double a,double b)
{
return ((double)rand()/RAND_MAX)*(b-a)+a;
}

double getArea(double r)
{
return PI * r * r;
}

void main()
{
Circle *arr = malloc(sizeof(Circle)*50); //create array
int i, maxIndex;
double maxArea;
for (i=0; i<50; i++)
{ //poulate array
arr[i].x = rand_float(100,900);
arr[i].y = rand_float(100,900);
arr[i].radius = rand_float(0,100);
}

maxArea = getArea(arr[0].radius);
maxIndex = 0;
for (i=1; i<50; i++) //find max area among all circle
if ( getArea(arr[i].radius) > maxArea)
{
maxArea = getArea(arr[i].radius);
maxIndex = i;
}
printf("Circle with largest area (%lf) \nhas center (%lf,%lf) and radius %lf\n", maxArea, arr[maxIndex].x, arr[maxIndex].y, arr[maxIndex].radius);
free(arr); //prevent memory leak
}

/*
sample output:
Circle with largest area (29386.402844)
has center (686.123529,625.250922) and radius 96.740514

*/