c - Printing content of 2D array (pointer of pointer) -

i defined function initialising 2d array through pointers , @ same time fell random values.

then print , don't see expected values. bug in code? i've been looking hours.

#define matrix_size 3  int **initialize_matrix(size_t m, size_t n){     int i1,i2;      int **ptr1=(int **)malloc(sizeof(int *)*m*n);     int *ptr2=(int *)malloc(sizeof(int)*m);      srand(time(0));     for(i1=0;i1<matrix_size;i1++){         for(i2=0;i2<matrix_size;i2++){             ptr2[i2]=rand()%10;             printf("%d ",ptr2[i2]);         }      }      for(i1=0;i1<matrix_size;i1++){         ptr1[i1]=ptr2+m*i1;     }     printf("\nfinished generating\n");      return ptr1; }  void print_matrix(int** matrix_to_print){     int i1,i2;      for(i1=0;i1<matrix_size;i1++)     for(i2=0;i2<matrix_size;i2++){         printf("%d ",matrix_to_print[i1][i2]);         if(i2==matrix_size-1)             printf("\n");       }  } 

this prints:

2 4 8
0 6 7 6 4 4 finished generating matriz 1: 6 4 4
135113 0 0 0 0 0

sample code

#include <stdio.h> #include <stdlib.h> #include <time.h>  #define matrix_size 3  int **initialize_matrix(size_t m, size_t n){ //make dynamic 2d array int a[m][n]     int i1,i2;      //there no need cast return value of malloc in c     int **ptr1=(int **)malloc(sizeof(int *)*m);      srand(time(0));     for(i1=0; i1<m; i1++){         ptr1[i1] = (int*)malloc(sizeof(int)*n);         for(i2=0; i2 < n; i2++){             ptr1[i1][i2]=rand()%10;             printf("%d ",ptr1[i1][i2]);         }      }     printf("\nfinished generating\n");      return ptr1; }  void print_matrix(int** matrix_to_print, size_t m, size_t n){     int i1,i2;      for(i1=0;i1<m;i1++){         for(i2=0; i2<n; i2++)             printf("%d ", matrix_to_print[i1][i2]);         printf("\n");     } }  int main(){     int **p = initialize_matrix(matrix_size, matrix_size);     print_matrix(p, matrix_size, matrix_size);     {   //deallocate         int i;         for(i = 0; < matrix_size; ++i)             free(p[i]);         free(p);     }      return 0; }