#include <stdio.h>
#include <sys/time.h>
#include <inttypes.h>

int main() {
	int key;
	int n;
	int tmp;
	uint64_t total = 0;
	int size = 100;
	int repeat_rate = 30000;
	struct timeval time1[size];
	struct timeval time2;
	struct timeval timediff;
	/* Add one because we drop the first key */
	size++;

	fprintf(stderr, "Press and hold ENTER key\n");
	tmp = gettimeofday(&time1[0], NULL);
	for (n = 1; n < size; n++) {
		key = getchar();
		tmp = gettimeofday(&time1[n], NULL);
	}
	/* Ignore the first key */
	for (n = 2; n < size; n++) {
		timediff.tv_sec = time1[n].tv_sec - time1[n-1].tv_sec;
		timediff.tv_usec = time1[n].tv_usec - time1[n-1].tv_usec;
		if (timediff.tv_usec < 0) {
			timediff.tv_usec += 1000000;
			timediff.tv_sec -= 1;
		}
		total += timediff.tv_usec;
		tmp = 0;
		if ((timediff.tv_usec > (repeat_rate + 1000)) || (timediff.tv_usec < (repeat_rate - 1000))) tmp = 1;
		printf("%ld.%06ld, %d\n", timediff.tv_sec, timediff.tv_usec, tmp);
	}
	printf("Total = %lu\n", total / (size - 1));
}