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

void *alloc_huge(size_t, int);

int main()
{
	//size_t n = 18400;
	size_t n = 3UL<<29;
	char *buf = alloc_huge(n, '1');
	buf[0] = '1';
	buf[1] = '.';
	buf[n-1] = 0;
	printf("%.21g (%zu)\n", strtod(buf, 0), n);
}