好問題

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

#pragma warning( disable : 4996 )

/*   i wrote

int divide(int all, int *arr,int len_front, int len_rear)
{
    int i,k,t;
    int mid = all / 2 ;   //find mid

    //for(int tmp=0;tmp<all;tmp++) printf("QQ  %d  QQ\n", arr[tmp]);




    int *l_arr = (int*)malloc(sizeof(int) * (mid + 1) );
    int *r_arr = (int*)malloc(sizeof(int) * (mid + 1) );


    for(i=1; i< (mid +1) ;i++)
    {
        l_arr[i] = arr[i];
        printf("front %d\n",arr[i]);
    }
    for(i = mid +1 ; i < all - 1; i++)
    {
        r_arr[i] = arr[i];
        printf("rear %d\n",arr[i]);
    }

    len_rear = (all -1 - mid -1);
    len_front = (mid +1 - 1);

    if(len_front != 1) {
        divide(mid, l_arr, len_front, len_rear);
        divide(mid, r_arr, len_front, len_rear);
    }
    else
    {
        printf("OMG plz \n");

    }



    free(l_arr);
    free(r_arr);

    return 0;
}

 */

int divide(int *arr, int front, int mid ,int rear)
{
    int i,k,t;

    int len_front = mid - front +1;
    int len_rear  = rear - mid ;

    int *l_arr = (int *)malloc(sizeof(int ) * (front +1));   // +1 because start form 0
    int *r_arr = (int *)malloc(sizeof(int ) * (len_rear));

    for(i=1; i<len_front +1; i++)
    {
        l_arr[i] = arr[front + i -1];
    }

    for(k=1; k<len_rear +1; k++)
    {
        r_arr[k] = arr[mid + k];
    }

    l_arr[len_front +1] = INT_MAX; r_arr[len_rear +1] = INT_MAX;

    i = k =1;

    for(t = front; t < rear +1; t++)
    {
        if( l_arr[i] <= r_arr[k] )
        {
            arr[t] = l_arr[i];
            i++;
        }
        else
        {
            arr[t] = r_arr[k];
            k++;

        }
    }

}


int merge_sort(int *arr, int front, int rear)
{
    int mid;
    if (front < rear)
    {
        mid = (front + rear) / 2;
        merge_sort(arr, front, mid);
        merge_sort(arr, front + 1, rear);
        divide(arr, front, mid, rear);

    }
}

int main()
{
    int counter = 1;
    int *dyarr = (int*)malloc(sizeof(int) *50010);
    int i;
    while(scanf("%d", &dyarr[counter++]) != EOF);


    merge_sort(dyarr, 1, counter);

    for (i = 0; i < counter+1; i++)
    {
        printf("%d\n", dyarr[i]);

    }

    free(dyarr);
    return 0;
}