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

int main() {

    unsigned long long int size = 0;
    unsigned int gib = 0;
    
    printf("please enter the number of gibibytes (GiB) you would like to allocate (1 GiB = 1073741824 bytes):\n> ");
    unsigned int digit = 0;
    while (1) {
        unsigned char input = getchar();
        if (input == '\n') break;
        if (input < '0' || input > '9') continue;

        if (digit > 0) gib = gib * 10;

        gib = gib + (unsigned int) input - 48;
        digit++;
    }

    size = (unsigned long long int) gib * 1024 * 1024 * 1024;

    printf("you are about to allocate %d GiB (%llu bytes) of heap memory. are you sure? (y/n)\n> ", gib, size);

    unsigned char input = getchar();
    if (input != 'y') return 0;
    while (getchar() != '\n');

    printf("please wait");
    unsigned long long int* wtf = (unsigned long long int*) malloc(size);

    for (unsigned long long int i = 0; i < size / sizeof(long long int); i++) {
        wtf[i] = 0x80085;
        if (i > 0 && i % (1024 * 1024 * 1024 / sizeof(long long int)) == 0) printf(".");
    }
    printf("\n");

    printf("%d GiB (%llu bytes) of heap memory has been allocated. you are insane.\n", gib, size);
    printf("press ENTER to release this memory, or CTRL+C to exit the program.\n");

    getchar();

    free(wtf);

    return 0;

}