Hackerrank small triangles, large triangles problem - c

Question

Link
here is link to question. In this question we have to sort the triangles based on their areas and then print out the dimensions of triangle in sorted format.
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
struct triangle
{
int a;
int b;
int c;
};
typedef struct triangle triangle;
void sort_by_area(triangle* tr, int n) {
/**
* Sort an array a of the length n
*/
double arr[n+1];
triangle temp;
for(int i=0;i<n;i++)
{
double area_2,p;
p=((tr[i].a+tr[i].b+tr[i].c)/2.0);
area_2=(p*(p-tr[i].a)*(p-tr[i].b)*(p-tr[i].c));
arr[i]=area_2;
}
for(int i=0;i<n-1;i++)
{
for(int j=i+1;j<n;j++)
{
if(arr[i]>arr[j])
{
temp=tr[i];
tr[i]=tr[j];
tr[j]=temp;
}
}
}
}
int main()
{
int n;
scanf("%d", &n);
triangle *tr = malloc(n * sizeof(triangle));
for (int i = 0; i < n; i++) {
scanf("%d%d%d", &tr[i].a, &tr[i].b, &tr[i].c);
}
sort_by_area(tr, n);
for (int i = 0; i < n; i++) {
printf("%d %d %d\n", tr[i].a, tr[i].b, tr[i].c);
}
return 0;
}
This is my code. Only sample testcase is getting passed with this code and all else testcases are wrong. can someone pls help me with this?

Answer 1

Thanks a lot guys for your help. finally with lots of debugging, i understood the error in my code. while swapping the structure array i was forgetting to swap the area array as well.Here is the code for this:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
struct triangle
{
int a;
int b;
int c;
};
typedef struct triangle triangle;
#define longlong int;
void swap(double *array,int i,int j)
{
int temp=array[i];
array[i]=array[j];
array[j]=temp;
}
void sort_by_area(triangle* tr, int n) {
double arr[n];
triangle temp;
for(int i=0;i<n;i++)
{
double area_2,p;
p=((tr[i].a+tr[i].b+tr[i].c)/2.0);
area_2=(p*(p-tr[i].a)*(p-tr[i].b)*(p-tr[i].c));
arr[i]=area_2;
/*storing square of area in a different array of different types of triangle*/
}
for(int i=0;i<n;i++)
{
for(int j=i+1;j<n;j++)
{
if(arr[i]>arr[j])
/*using bubble sort comparing the area of subsequent triangles and if area of subsequent triangles are found to be greater than the previous one then swapping the areas as well as the structure array*/
{ swap(arr,i,j);
temp=tr[i];
tr[i]=tr[j];
tr[j]=temp;
}
}
}
}
int main()
{
int n;
scanf("%d", &n);
triangle *tr = malloc(n * sizeof(triangle));
for (int i = 0; i < n; i++) {
scanf("%d%d%d", &tr[i].a, &tr[i].b, &tr[i].c);
}
sort_by_area(tr, n);
for (int i = 0; i < n; i++) {
printf("%d %d %d\n", tr[i].a, tr[i].b, tr[i].c);
}
return 0;
}