Preprotsessor va ko'p faylli loyiha

#include <stdio.h>

#define PI 3.14159
#define MAKS_TALABA 50
#define SALOM "Assalomu alaykum"

int main(void) {
    printf("%s!\n", SALOM);
    printf("PI = %.5f\n", PI);
    printf("Maksimal talaba: %d\n", MAKS_TALABA);
    printf("Aylana uzunligi: %.2f\n", 2 * PI * 5.0);

    return 0;
}

#include <stdio.h>

#define KVADRAT(x) ((x) * (x))
#define MAKS(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b)  ((a) < (b) ? (a) : (b))

int main(void) {
    printf("KVADRAT(5)      = %d\n", KVADRAT(5));
    printf("KVADRAT(2 + 3)  = %d\n", KVADRAT(2 + 3));
    printf("MAKS(10, 25)    = %d\n", MAKS(10, 25));
    printf("MIN(10, 25)     = %d\n", MIN(10, 25));

    return 0;
}

#include <stdio.h>

#define ELEMENTLAR(m) (sizeof(m) / sizeof((m)[0]))

#define TEKSHIR(shart) \
    do { \
        if (!(shart)) { \
            fprintf(stderr, "Tekshiruv buzildi: %s (%s:%d)\n", \
                    #shart, __FILE__, __LINE__); \
        } \
    } while (0)

int main(void) {
    int ballar[] = {85, 92, 78, 95, 88};

    printf("Elementlar soni: %zu\n", ELEMENTLAR(ballar));

    int yosh = 25;
    TEKSHIR(yosh > 18);
    TEKSHIR(yosh > 100);

    return 0;
}

Elementlar soni: 5
Tekshiruv buzildi: yosh > 100 (makros.c:22)

#include <stdio.h>

#define NOSOZLIK 1

int main(void) {
#if NOSOZLIK
    printf("[nosozlik] Dastur boshlandi\n");
#endif

    printf("Asosiy ish bajarilmoqda\n");

#ifdef _WIN32
    printf("Windows tizimi\n");
#elif defined(__linux__)
    printf("Linux tizimi\n");
#elif defined(__APPLE__)
    printf("macOS tizimi\n");
#else
    printf("Noma'lum tizim\n");
#endif

#if NOSOZLIK
    printf("[nosozlik] Dastur tugadi\n");
#endif

    return 0;
}

#ifndef TALABA_H
#define TALABA_H

#define MAKS_ISM 50

typedef struct {
    char ism[MAKS_ISM];
    int yosh;
    double baho;
} Talaba;

/* Yangi talaba yaratadi. */
Talaba talaba_yarat(const char *ism, int yosh, double baho);

/* Talabani ekranga chiqaradi. */
void talaba_chiqar(const Talaba *t);

/* Guruh o'rtacha bahosini hisoblaydi. Guruh bo'sh bo'lsa 0 qaytaradi. */
double guruh_ortachasi(const Talaba guruh[], int soni);

#endif /* TALABA_H */

#include <stdio.h>
#include <string.h>
#include "talaba.h"

Talaba talaba_yarat(const char *ism, int yosh, double baho) {
    Talaba yangi;

    strncpy(yangi.ism, ism, MAKS_ISM - 1);
    yangi.ism[MAKS_ISM - 1] = '\0';
    yangi.yosh = yosh;
    yangi.baho = baho;

    return yangi;
}

void talaba_chiqar(const Talaba *t) {
    printf("%-20s %3d %6.2f\n", t->ism, t->yosh, t->baho);
}

double guruh_ortachasi(const Talaba guruh[], int soni) {
    if (soni <= 0) {
        return 0.0;
    }

    double yigindi = 0.0;

    for (int i = 0; i < soni; i++) {
        yigindi += guruh[i].baho;
    }

    return yigindi / soni;
}

#include <stdio.h>
#include "talaba.h"

int main(void) {
    Talaba guruh[3];

    guruh[0] = talaba_yarat("Husanboy Qodirov", 25, 4.60);
    guruh[1] = talaba_yarat("Malika Yusupova", 21, 4.90);
    guruh[2] = talaba_yarat("Nodira Sobirova", 24, 4.30);

    printf("%-20s %3s %6s\n", "Talaba", "Yosh", "Baho");
    printf("-------------------------------\n");

    for (int i = 0; i < 3; i++) {
        talaba_chiqar(&guruh[i]);
    }

    printf("-------------------------------\n");
    printf("O'rtacha: %.2f\n", guruh_ortachasi(guruh, 3));

    return 0;
}

gcc -std=c17 -Wall -Wextra -c talaba.c -o talaba.o
gcc -std=c17 -Wall -Wextra -c main.c   -o main.o
gcc talaba.o main.o -o dastur
./dastur

Talaba               Yosh   Baho
-------------------------------
Husanboy Qodirov      25   4.60
Malika Yusupova       21   4.90
Nodira Sobirova       24   4.30
-------------------------------
O'rtacha: 4.60

gcc -std=c17 -Wall -Wextra talaba.c main.c -o dastur

#ifndef TALABA_H
#define TALABA_H

/* ... e'lonlar ... */

#endif

/* talaba.c ichida */

static int hisoblagich = 0;          /* faqat shu faylda ko'rinadi */

static void ichki_yordamchi(void) {  /* faqat shu faylda chaqiriladi */
    hisoblagich++;
}

CC = gcc
CFLAGS = -std=c17 -Wall -Wextra -g
MAQSAD = dastur
MANBALAR = main.c talaba.c
OBYEKTLAR = $(MANBALAR:.c=.o)

all: $(MAQSAD)

$(MAQSAD): $(OBYEKTLAR)
    $(CC) $(OBYEKTLAR) -o $@

%.o: %.c
    $(CC) $(CFLAGS) -c $< -o $@

main.o: main.c talaba.h
talaba.o: talaba.c talaba.h

tozala:
    rm -f $(OBYEKTLAR) $(MAQSAD)

ishga: $(MAQSAD)
    ./$(MAQSAD)

.PHONY: all tozala ishga

make            # yig'adi
make ishga      # yig'adi va ishga tushiradi
make tozala     # oraliq fayllarni o'chiradi

loyiha/
├── Makefile
├── src/
│   ├── main.c
│   ├── talaba.c
│   └── hisobot.c
├── include/
│   ├── talaba.h
│   └── hisobot.h
├── tests/
│   └── talaba_test.c
└── build/
    └── (yig'ilgan fayllar)

gcc -std=c17 -Wall -Iinclude src/*.c -o build/dastur