Standart kutubxona

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

int main(void) {
    printf("atoi(\"42\")      = %d\n", atoi("42"));
    printf("atof(\"3.14\")    = %.2f\n", atof("3.14"));

    char *qolgan;
    long son = strtol("1234abc", &qolgan, 10);
    printf("strtol          = %ld, qolgan: \"%s\"\n", son, qolgan);

    long ikkilik = strtol("1011", NULL, 2);
    printf("ikkilik 1011    = %ld\n", ikkilik);

    long onoltilik = strtol("ff", NULL, 16);
    printf("o'n oltilik ff  = %ld\n", onoltilik);

    return 0;
}

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

int main(void) {
    srand(42);              /* qat'iy urug' - natija takrorlanadi */

    printf("Besh tasodifiy son (1-100):\n");

    for (int i = 0; i < 5; i++) {
        int son = rand() % 100 + 1;
        printf("  %d\n", son);
    }

    return 0;
}

#include <stdio.h>
#include <math.h>

/* -std=c17 qat'iy rejimida M_PI va M_E aniqlanmagan bo'lishi mumkin */
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
#ifndef M_E
#define M_E  2.71828182845904523536
#endif

int main(void) {
    printf("sqrt(16)      = %.2f\n", sqrt(16.0));
    printf("pow(2, 10)    = %.0f\n", pow(2.0, 10.0));
    printf("fabs(-7.5)    = %.2f\n", fabs(-7.5));
    printf("ceil(4.2)     = %.0f\n", ceil(4.2));
    printf("floor(4.8)    = %.0f\n", floor(4.8));
    printf("round(4.5)    = %.0f\n", round(4.5));
    printf("fmod(17, 5)   = %.2f\n", fmod(17.0, 5.0));
    printf("log(M_E)      = %.2f\n", log(M_E));
    printf("log10(1000)   = %.2f\n", log10(1000.0));

    double burchak = M_PI / 6.0;                   /* 30 daraja */
    printf("sin(30 daraja) = %.4f\n", sin(burchak));
    printf("cos(30 daraja) = %.4f\n", cos(burchak));

    return 0;
}

#include <stdio.h>
#include <ctype.h>

int main(void) {
    const char *matn = "Salom C-2026!";

    printf("%-8s %-6s %-6s %-6s %-6s\n",
           "Belgi", "harf", "raqam", "probel", "katta");
    printf("----------------------------------------\n");

    for (int i = 0; matn[i] != '\0'; i++) {
        unsigned char b = (unsigned char) matn[i];

        printf("%-8c %-6s %-6s %-6s %-6s\n",
               matn[i],
               isalpha(b) ? "ha" : "-",
               isdigit(b) ? "ha" : "-",
               isspace(b) ? "ha" : "-",
               isupper(b) ? "ha" : "-");
    }

    return 0;
}

#include <stdio.h>
#include <time.h>

int main(void) {
    /* qat'iy vaqt - natija takrorlanadigan bo'lsin */
    time_t vaqt = 1789000000;
    struct tm *mahalliy = gmtime(&vaqt);

    printf("Yil    : %d\n", mahalliy->tm_year + 1900);
    printf("Oy     : %d\n", mahalliy->tm_mon + 1);
    printf("Kun    : %d\n", mahalliy->tm_mday);
    printf("Soat   : %02d:%02d:%02d\n",
           mahalliy->tm_hour, mahalliy->tm_min, mahalliy->tm_sec);

    char bufer[64];
    strftime(bufer, sizeof(bufer), "%d.%m.%Y %H:%M", mahalliy);
    printf("Formatlangan: %s\n", bufer);

    return 0;
}

#include <stdio.h>
#include <time.h>

int main(void) {
    clock_t boshlandi = clock();

    long long yigindi = 0;
    for (long long i = 0; i < 50000000LL; i++) {
        yigindi += i;
    }

    clock_t tugadi = clock();
    double soniya = (double) (tugadi - boshlandi) / CLOCKS_PER_SEC;

    printf("Yig'indi hisoblandi: %lld\n", yigindi);
    printf("Vaqt 0 dan katta   : %s\n", (soniya >= 0.0) ? "ha" : "yo'q");

    return 0;
}

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

int solishtir_osib(const void *a, const void *b) {
    int birinchi = *(const int *) a;
    int ikkinchi = *(const int *) b;

    if (birinchi < ikkinchi) return -1;
    if (birinchi > ikkinchi) return 1;
    return 0;
}

int solishtir_kamayib(const void *a, const void *b) {
    return solishtir_osib(b, a);
}

int main(void) {
    int sonlar[] = {85, 92, 78, 95, 88, 61, 100, 73};
    int soni = sizeof(sonlar) / sizeof(sonlar[0]);

    qsort(sonlar, soni, sizeof(sonlar[0]), solishtir_osib);

    printf("O'sish tartibida  : ");
    for (int i = 0; i < soni; i++) printf("%d ", sonlar[i]);

    qsort(sonlar, soni, sizeof(sonlar[0]), solishtir_kamayib);

    printf("\nKamayish tartibida: ");
    for (int i = 0; i < soni; i++) printf("%d ", sonlar[i]);
    printf("\n");

    return 0;
}

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

typedef struct {
    char ism[30];
    int yosh;
    double baho;
} Talaba;

int baho_boyicha(const void *a, const void *b) {
    const Talaba *x = a;
    const Talaba *y = b;

    if (x->baho < y->baho) return 1;      /* kamayish tartibi */
    if (x->baho > y->baho) return -1;
    return 0;
}

int ism_boyicha(const void *a, const void *b) {
    const Talaba *x = a;
    const Talaba *y = b;

    return strcmp(x->ism, y->ism);
}

void chiqar(const char *sarlavha, const Talaba guruh[], int soni) {
    printf("%s\n", sarlavha);
    for (int i = 0; i < soni; i++) {
        printf("  %-18s %3d %6.2f\n", guruh[i].ism, guruh[i].yosh, guruh[i].baho);
    }
}

int main(void) {
    Talaba guruh[] = {
        {"Husanboy Qodirov", 25, 4.60},
        {"Malika Yusupova",  21, 4.90},
        {"Nodira Sobirova",  24, 4.30},
        {"Aziza Tosheva",    22, 4.10}
    };

    int soni = sizeof(guruh) / sizeof(guruh[0]);

    qsort(guruh, soni, sizeof(guruh[0]), baho_boyicha);
    chiqar("Baho bo'yicha:", guruh, soni);

    qsort(guruh, soni, sizeof(guruh[0]), ism_boyicha);
    chiqar("\nIsm bo'yicha:", guruh, soni);

    return 0;
}

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

int solishtir(const void *a, const void *b) {
    int x = *(const int *) a;
    int y = *(const int *) b;

    if (x < y) return -1;
    if (x > y) return 1;
    return 0;
}

int main(void) {
    int sonlar[] = {61, 73, 78, 85, 88, 92, 95, 100};   /* saralangan! */
    int soni = sizeof(sonlar) / sizeof(sonlar[0]);

    int qidirilayotgan[] = {88, 50};

    for (int i = 0; i < 2; i++) {
        int *natija = bsearch(&qidirilayotgan[i], sonlar, soni,
                              sizeof(sonlar[0]), solishtir);

        if (natija != NULL) {
            printf("%d topildi, indeks: %ld\n",
                   qidirilayotgan[i], natija - sonlar);
        } else {
            printf("%d topilmadi\n", qidirilayotgan[i]);
        }
    }

    return 0;
}

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

int main(void) {
    int manba[5] = {1, 2, 3, 4, 5};
    int maqsad[5];

    memcpy(maqsad, manba, sizeof(manba));
    printf("memcpy  : ");
    for (int i = 0; i < 5; i++) printf("%d ", maqsad[i]);

    memset(maqsad, 0, sizeof(maqsad));
    printf("\nmemset  : ");
    for (int i = 0; i < 5; i++) printf("%d ", maqsad[i]);

    printf("\nmemcmp  : %s\n",
           memcmp(manba, manba, sizeof(manba)) == 0 ? "bir xil" : "farqli");

    char matn[20] = "abcdefgh";
    memmove(matn + 2, matn, 6);      /* ustma-ust joylar uchun xavfsiz */
    matn[8] = '\0';
    printf("memmove : %s\n", matn);

    return 0;
}

#include <stdio.h>
#include <assert.h>

double ortacha(const int massiv[], int soni) {
    assert(massiv != NULL);
    assert(soni > 0);

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

    return (double) yigindi / soni;
}

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

    printf("O'rtacha: %.2f\n", ortacha(ballar, 3));
    return 0;
}

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

void tozalash(void) {
    printf("Tozalash bajarildi\n");
}

int main(void) {
    atexit(tozalash);          /* chiqishda avtomatik chaqiriladi */

    printf("Asosiy ish\n");

    if (0) {
        exit(EXIT_FAILURE);    /* istalgan joydan chiqish */
    }

    printf("Dastur tugadi\n");
    return EXIT_SUCCESS;
}