Funksiyalar

#include <stdio.h>

int qoshish(int birinchi, int ikkinchi) {
    return birinchi + ikkinchi;
}

double aylana_yuzasi(double radius) {
    return 3.14159 * radius * radius;
}

void salomlash(const char *ism) {
    printf("Salom, %s!\n", ism);
    /* void - hech narsa qaytarmaydi */
}

int main(void) {
    printf("7 + 5 = %d\n", qoshish(7, 5));
    printf("Yuza  = %.2f\n", aylana_yuzasi(3.0));
    salomlash("Husanboy");

    return 0;
}

#include <stdio.h>

/* prototiplar - funksiyalar haqida oldindan xabar */
int qoshish(int a, int b);
int kopaytirish(int a, int b);

int main(void) {
    printf("%d\n", qoshish(3, 4));
    printf("%d\n", kopaytirish(3, 4));
    return 0;
}

/* aniqlanishi - keyinroq */
int qoshish(int a, int b) {
    return a + b;
}

int kopaytirish(int a, int b) {
    return a * b;
}

#include <stdio.h>

void ozgartirishga_urinish(int son) {
    son = 100;
    printf("  Funksiya ichida : %d\n", son);
}

int main(void) {
    int qiymat = 5;

    printf("Chaqiruvdan oldin : %d\n", qiymat);
    ozgartirishga_urinish(qiymat);
    printf("Chaqiruvdan keyin : %d\n", qiymat);

    return 0;
}

#include <stdio.h>

void nolla(int massiv[], int soni) {
    for (int i = 0; i < soni; i++) {
        massiv[i] = 0;
    }
}

int yigindi(const int massiv[], int soni) {
    int jami = 0;

    for (int i = 0; i < soni; i++) {
        jami += massiv[i];
    }

    return jami;
}

int main(void) {
    int ballar[5] = {85, 92, 78, 95, 88};

    printf("Yig'indi: %d\n", yigindi(ballar, 5));

    nolla(ballar, 5);
    printf("Nollangandan keyin: %d\n", yigindi(ballar, 5));

    return 0;
}

#include <stdio.h>

int global_hisob = 0;        /* butun faylda ko'rinadi */

void oshir(void) {
    global_hisob++;          /* global o'zgaruvchiga murojaat */
    int mahalliy = 10;       /* faqat shu funksiyada */
    printf("  mahalliy = %d\n", mahalliy);
}

int main(void) {
    oshir();
    oshir();
    oshir();

    printf("global_hisob = %d\n", global_hisob);
    /* printf("%d\n", mahalliy);   XATO: bu yerda mavjud emas */

    return 0;
}

#include <stdio.h>

void oddiy_hisoblagich(void) {
    int hisob = 0;
    hisob++;
    printf("  oddiy  : %d\n", hisob);
}

void static_hisoblagich(void) {
    static int hisob = 0;    /* faqat bir marta yaratiladi */
    hisob++;
    printf("  static : %d\n", hisob);
}

int main(void) {
    for (int i = 0; i < 3; i++) {
        oddiy_hisoblagich();
        static_hisoblagich();
    }

    return 0;
}

#include <stdio.h>

long long faktorial(int n) {
    if (n <= 1) {
        return 1;            /* tayanch holat */
    }
    return n * faktorial(n - 1);   /* o'zini chaqiradi */
}

int main(void) {
    for (int i = 1; i <= 10; i++) {
        printf("%2d! = %lld\n", i, faktorial(i));
    }

    return 0;
}

#include <stdio.h>

long long fibonachchi_rekursiv(int n) {
    if (n <= 1) {
        return n;
    }
    return fibonachchi_rekursiv(n - 1) + fibonachchi_rekursiv(n - 2);
}

long long fibonachchi_sikl(int n) {
    if (n <= 1) {
        return n;
    }

    long long oldingi = 0, joriy = 1;

    for (int i = 2; i <= n; i++) {
        long long keyingi = oldingi + joriy;
        oldingi = joriy;
        joriy = keyingi;
    }

    return joriy;
}

int main(void) {
    int n = 30;

    printf("Rekursiv : fib(%d) = %lld\n", n, fibonachchi_rekursiv(n));
    printf("Sikl     : fib(%d) = %lld\n", n, fibonachchi_sikl(n));

    return 0;
}

#include <stdio.h>

/* 1-usul: ko'rsatkich orqali (12-bo'limda batafsil) */
void bol(int a, int b, int *butun, int *qoldiq) {
    *butun = a / b;
    *qoldiq = a % b;
}

/* 2-usul: strukturada (15-bo'limda batafsil) */
struct Natija {
    int butun;
    int qoldiq;
};

struct Natija bol2(int a, int b) {
    struct Natija n;
    n.butun = a / b;
    n.qoldiq = a % b;
    return n;
}

int main(void) {
    int butun, qoldiq;
    bol(17, 5, &butun, &qoldiq);
    printf("1-usul: %d butun, %d qoldiq\n", butun, qoldiq);

    struct Natija n = bol2(17, 5);
    printf("2-usul: %d butun, %d qoldiq\n", n.butun, n.qoldiq);

    return 0;
}