#include<iostream>
using namespace std;

/*
 * Base case:  The case where we stop recursion
 * 	If we've reached that case, we return WITHOUT calling ourselves again
 * General case, or recursive step
 * 	This must move toward being done
 * 	Includes a recursive call (a call to the function we're writing)
 */

void pia_recur(int *array, size_t length){
	if(!length)
		return;
	cout << *array << ", ";
	pia_recur(array + 1, length - 1);
	
}

void print_int_array(int* array, size_t length){
	// Convert this to a do while loop
	cout << "[";
	pia_recur(array, length);
	cout << "\b\b]\n";
}


void task_one(int startpoint){
	if(startpoint <= 0) // Called the base case
		return;
	task_one(startpoint - 1);
	cout << startpoint - 1 << " ";
}

void task_two(int *array, size_t length){
	if(length == 0) {
		cout << "\n";
		return;
	}
	cout << *array << " ";
	// Same as:  cout << array[0] << " ";
	task_two(array + 1, length - 1);
	// Same as:  task_two(&array[1], length - 1);
}

void task_three(int end_number){
	if(end_number < 0){
		return;
	}
	task_three(end_number - 1);
	cout << end_number + 1 << " ";
}

void task_four(int *numbers, size_t length, int multiplier){
	if(!length){
		cout << "\n";
		return;
	}
	cout << *numbers * multiplier << " ";
	task_four(numbers + 1, length - 1, multiplier);
}

int main(){
	// Task One
	for(int i = 0; i < 10; i++)
		cout << i << " ";
	cout << "\n";

	// Recursive solution
	task_one(10);
	cout << "\n";


	// Task Two
	int numbers[] = {3, 6, 9, 12, 15};
	int j = 0;
	do {
		cout << numbers[j] << " ";
		j++;
	} while(j < 5);
	cout << "\n";

	// Recursive solution
	task_two(numbers, 5);
	
	// Task Three
	int k = 0;
	while(true){
		if(k++ > 10)
			break;
		cout << k << " ";
	}
	cout << endl;

	// Recursive Solution
	task_three(10);
	cout << "\n";

	// Task Four
	for(int i : numbers)
		cout << i*5 << " ";
	cout << "\n";

	// Recursive Solution
	task_four(numbers, 5, 5);


	// Task Five
	int l = 0;
top:
	cout << numbers[l] * 100 << " ";
	l++;
	if(l < 5)
		goto top;
	cout << "\n";

	// Recursive Solution
	task_four(numbers, 5, 100);

	print_int_array(numbers, 5);
	
	return 0;
}