이거 왜 질문이 두번씩 뜰까요

int main()
{
	int c = 0;
	char z;

	while (1) 
	{
		printf("Enter the letter of your choice : \na. averngers	b. beep\nc. count	q. quit\n");

		z = getchar();

		if (z == 'a')
			printf("Avengers assemble!\n");


		else if (z == 'b')
			printf("\a");

		else if (z == 'c')
		{
			printf("Enter an integer : ");
			scanf("%d", &c);
			for (int i = 1; c >= i; ++i)
				printf("%d\n", i);
		}
		else if (z == 'q')		
			break;
	}


	return 0;

}

왜 질문이 2번씩 나올까요