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

void fizzbuzz(int n)
{
    int i;
    for (i = 1; i <= n; i++)
    {
        if (i%3 == 0 || i%5 == 0)
        {
            if (i % 3 == 0 && i % 5 == 0)
                printf("fizzbuzz\n");
            else if (i%3==0)
                printf("fizz\n");
            else
                printf("buzz\n");
        }
        else
        {
            printf("%d\n", i);
        }
    }
}

#define BUF_SIZE 1024

void fizzbuzz_fast(int n)
{
    int i;
    
    char str[BUF_SIZE];
    int curr_str_pos = 0;

    for (i = 1; i <= n; i++)
    {
        if (i % 3 == 0 || i % 5 == 0)
        {
            char* strToPrint;
            int result;

            if (i % 3 == 0 && i % 5 == 0)
            {
                strToPrint = "fizzbuzz\n";
            }
            else if (i % 3 == 0)
            {
                strToPrint = "fizz\n";
            }
            else
            {
                strToPrint = "buzz\n";
            }

            result = snprintf(str + curr_str_pos, BUF_SIZE - curr_str_pos, "%s", strToPrint);
            if (!(result < BUF_SIZE - curr_str_pos))
            {
                printf("%s", str);
                curr_str_pos = 0;
                result = snprintf(str + curr_str_pos, BUF_SIZE - curr_str_pos, "%s", strToPrint);
            }
            curr_str_pos += result;
        }
        else
        {
            int result;
            result = snprintf(str + curr_str_pos, BUF_SIZE - curr_str_pos, "%d\n", i);
            
            if (!(result < BUF_SIZE - curr_str_pos))
            {
                printf("%s", str);
                curr_str_pos = 0;
                result = snprintf(str + curr_str_pos, BUF_SIZE - curr_str_pos, "%d\n", i);
            }
            curr_str_pos += result;
        }
    }

    if (curr_str_pos != 0)
    {
        printf("%s", str);
    }
}

void fizzbuzz_branchless(int n)
{
    char *zzc[]={"fizz\n","buzz\n","fizzbuzz\n","%d\n"};
    int zxc[]={3,0,0,1,0,0,2};
    for (int i = 1; i < n; ++i)
    {
        int a=i%3==0;
        int b=i%5==0;
        int t=b^a;
        printf(zzc[zxc[a<<2|(b<<1)|t]],i);
    }
}

int main(int argc, char **argv)
{
	(void)argc;
	(void)argv;
	
    int n;
	
	clock_t reg_start, reg_end, branchless_start, branchless_end, fast_start, fast_end;
	
    printf("How many fizzbuzzes?: ");
    int ret = scanf("%d", &n);
    if (ret)
    {
        reg_start = clock();
        fizzbuzz(n);
        reg_end = clock();

        branchless_start = clock();
        fizzbuzz_branchless(n);
        branchless_end = clock();

        fast_start = clock();
        fizzbuzz_fast(n);
        fast_end = clock();

        printf("regular time: %ld\n", reg_end - reg_start);
        printf("branchless time: %ld\n", branchless_end - branchless_start);
        printf("fast time: %ld\n", fast_end - fast_start);
    }
    else
    {
        printf("Invalid input\n");
    }
    
    return 0;
}