VitasLab4(files)

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
#include <string.h>

#define HEADOUTFORMAT "%-15s%-15s%-15s%-15s%-15s\n"
#define OUTFORMAT "%-15s%-15d%-15d%-15d%-15d\n"

typedef struct {
    char lastName[64];
    int group, gi, gim, get;
} person;

void print(person *persons, int n);

int input(person *persons)
{
    int n, i;
    FILE *file = fopen("input.bin", "wb");
    if (!file) { printf("File open error"); _getch(); return 0; }

    printf("input n: "); scanf("%d", &n);
    persons = (person*) malloc(sizeof(person) *n);

    printf("Input persons (by format - LastName Group GradeInfr GradeInMova GradeEcoTeo):\n");
    for (i = 0; i < n; i++)
    {
        scanf("%s %d %d %d %d", persons[i].lastName, &persons[i].group, &persons[i].gi, &persons[i].gim, &persons[i].get);
    }

    for (i = 0; i < n; i++)
    {
        fwrite(&persons[i], sizeof(person), 1, file);
    }

    fclose(file);
    return n;
}

person* read(int count)
{
    int i = 0;
    FILE *file;
    person *persons = NULL;
    file = fopen("input.bin", "rb");

    if (!file) { printf("File open error"); _getch(); return 0; }

    persons = (person*) malloc(sizeof(person) *count);
    //if (fread(&persons, sizeof(person), count, file) == 0) return NULL;
    while (!feof(file))
    {
        fread(&persons[i], sizeof(person), 1, file);
        i++;
    }


    fclose(file);
    return persons;
}


void print(person* persons, int n)
{
    int i = 0;
    FILE *file = fopen("output.txt", "w");
    if (!file) { printf("File open error"); _getch(); return; }

    if (!persons) return;
    putchar('\n'); printf(HEADOUTFORMAT, "LastName", "Group", "GradeInfr", "GradeInMova", "GradeEcoTeo");
    fprintf(file, HEADOUTFORMAT, "LastName", "Group", "GradeInfr", "GradeInMova", "GradeEcoTeo");
    for (i = 0; i < n; i++)
    {
        printf(OUTFORMAT, persons[i].lastName, persons[i].group, persons[i].gi, persons[i].gim, persons[i].get);
        fprintf(file, OUTFORMAT, persons[i].lastName, persons[i].group, persons[i].gi, persons[i].gim, persons[i].get);
    }

    fclose(file);
}


int supermans(person *persons, int n, int g)
{
    int i = 0, c = 0;
    FILE *file = fopen("ageout.txt", "w");
    if (!file) { printf("File open error"); _getch(); return 0; }

    if (!persons) return -1;
    printf(HEADOUTFORMAT, "LastName", "Group", "GradeInfr", "GradeInMova", "GradeEcoTeo");
    fprintf(file, HEADOUTFORMAT, "LastName", "Group", "GradeInfr", "GradeInMova", "GradeEcoTeo");
    for (i = 0; i < n; i++)
        if (persons[i].group == g && persons[i].gim == 5 && persons[i].gi == 5 && persons[i].get == 5)
        {
            printf(OUTFORMAT, persons[i].lastName, persons[i].group, persons[i].gi, persons[i].gim, persons[i].get);
            fprintf(file, OUTFORMAT, persons[i].lastName, persons[i].group, persons[i].gi, persons[i].gim, persons[i].get);
            c++;
        }

    fclose(file);
    return c;
}

person *psort(person *p, int n)
{
    int i, j; person tmp;
    for (i = 0; i < n; i++)
    {
        for (j = i + 1; j < n; j++)
        {
            if (strcmp(p[i].lastName, p[j].lastName) > 0)
            {
                tmp = p[i];
                p[i] = p[j];
                p[j] = tmp;
            }
        }
    }

    return p;
}

int main()
{
    int n = 1, g = 0;
    person *p = NULL;
    printf("input group: ");
    scanf("%d", &g);
    n = input(p);
    supermans(p, n, g);
    p = read(n);
    p = psort(p, n);
    print(p, n);

    _getch();
    return 0;
}