Треугольники,ромбы

#include <stdio.h>

#define SIZE 5
//https://otvet.mail.ru/question/217487097

int main()
{
    int sum,i, j,arr[SIZE][SIZE]={1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25};
    //{11,12,13,14,15,21,22,23,24,25,31,32,33,34,35,41,42,43,44,45,51,52,53,54,55};
    //{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25};
    sum = 0;

   for(i=0;i<SIZE/2+1;i++)//
   {
       for(j=i;j<SIZE-i;j++)
       {
           printf("%d\t",arr[i][j]);
       }
        printf("\n");

   }
   for(i=SIZE/2+1;i<SIZE;i++)
   {
       printf("\niiii-%d\n",i);
       for(j=SIZE/2+2-i;j<SIZE/2+i-1;j++)
       {
           printf("%d\t",arr[i][j]);

       }
        printf("\n");
   }



    return 0;
}