Форматирование файла целых чисел, полученных с помощью датчика случайных чисел, нахождение контрольной суммы

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <memory.h>
#include <time.h>
 
#define N 30
 
int main(int argc, char* argv[])
{
    FILE *fp_in = NULL, *fp_out = NULL;
 
    // Opening file for writing a sequence of numbers into it
    if ((fp_out = fopen("data.txt","w")) == NULL)
    {
        // If failed, printing error message
        printf("Unable to open file for writing...\n");
        return 1;
    }
 
    fclose(fp_out);
 
    // initializing random generator
    srand(time(NULL));
 
    // Generating of N random values and printing it to file
    for (int t = 0; t < N; t++)
        fprintf(fp_out,"%d ",rand() % N + 1);
 
    // Opening file for reading a sequence of numbers
    if ((fp_in = fopen("data.txt","r")) == NULL)
    {
        // If failed, printing error message
        printf("Unable to open file for reading...\n");
        return 1;
    }
 
    int* A = new int[N];
    memset((void*)A, 0x00, sizeof(int) * N);
 
    // Reading each value from a sequence in the file and
    // determining minimum and maximum values
    int min = 0, max = 0, x = 0;
    for (int r = 0; r < N; r++)
    {
        int val = 0;
        fscanf(fp_in,"%d ",&val);
 
        if (val > max || max == 0) max = val;
        if (val < min || min == 0) min = val;
        if (val != -1) A[x++] = val;
    }
 
    int i = 0, sum = 0;
    while (i < N) sum+=A[i++];
 
    if (sum >= min) printf("checksum is greater or equal to minimal\n");
    else if (sum < min) printf("checksum is less than minimal\n");
    else if (sum >= max) printf("checksum is greater or equal to maximal\n");
    else if (sum < max) printf("checksum is less than maximal\n");
 
    fclose(fp_in);
 
    _getch();
 
    return 0;
}