#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>

int main()
{
                int x, y, i, j;
                int **ar_ptr1, **ar_ptr2;
                
                printf("Input x : "), scanf("%d", &x);
                printf("Input y : "), scanf("%d", &y);

                ar_ptr1=(int**)malloc(sizeof(int)*x);
                for (i=0; i<x; i++)
                        ar_ptr1[i]=(int*)malloc(sizeof(int)*y);
                ar_ptr2=(int**)malloc(sizeof(int)*y);
                for (i=0; i<y; i++)
                        ar_ptr2[i]=(int*)malloc(sizeof(int)*x);

                for (i=0; i<x; i++)
                {
                                for (j=0; j<y; j++)
                                {
                                        printf("Input ar_ptr1[%d][%d] : ", i, j), scanf("%d", &ar_ptr1[i][j]);
                                }
                }

                for (i=0; i<y; i++)
                {
                        for (j=x; 0<j; j--)
                        {
                                ar_ptr2[i][j]=ar_ptr1[j][i];        
                        }
                }


                for(i=0; i<x; i++)
                {
                                for(j=0; j<y; j++)
                                {
                                        printf("%d ", ar_ptr1[i][j]);
                                        
                                }
                                printf("\n");
                }
                printf("converted\n");
                for(i=0; i<y; i++)
                {
                                for(j=0; j<x; j++)
                                {
                                        printf("%d ", ar_ptr2[i][j]);
                                        
                                }
                                printf("\n");
                }

        system("pause");
        return 0;
}


동적할당시킨 2차원 배열 ar_ptr1에 숫자 입력받고 그걸 90도 회전시켜서 ar_ptr2에 저장하고 각각 출력하는건데요

컴파일까지는 에러없이 잘만 되는데 실행만 시키면 숫자들을 입력받고 난 뒤에
segmentation error (core dumped)
라고 뜨네여

뭐가 문제인건가여