SSTF

gistfile1.txt

int SSTF(int start_index, int a[]) {

/*
				START INITILIZATION
*/
		int distance = 0;
		int counter_limit = 0;
		int current_value = a[start_index];
		int current_index = start_index;
		// keep track of visited locations
		int already_visited[1001];
		int right_value = -1;
		int left_value = -1;
		int right_index = -1;
		int left_index = -1;

		for (int i = 0; i < 1001; ++i) {
			already_visited[i] = 0;
		}

		//mark first address as visited
		already_visited[current_index] = 1;
		/*
						END INITILIZATION
		*/

		/*
						START LOOP
		*/
		while(counter_limit < 1001){

		// get right index, check bounds first
		if ((start_index - 1) > 0) {
			// in bounds
			right_index = (start_index - 1);
		} else{
			// out of bounds
			right_index = -1;
		}

		// get left index, check bounds first
		if ((start_index + 1) < 1001)
		{
			left_index = (start_index + 1);
		} else{
			left_index = -1;
		}

		// if left and right are within bounds
		if(right_index != -1 && left_index != -1)
		{
			left_value = a[left_index];
			right_value = a[right_index];

			int left_distance = abs((current_value - left_value));
			int right_distance = abs(current_value - right_value));

			// if the left value is closer
			if (left_distance < right_distance) {
				// update distance
				distance += left_distance;
				already_visited[left_index] = 1;
				current_index = left_index;
			} else {	// if the right value is closer
				// update distance
				distance += right_distance;
				// mark visited
				already_visited[right_index] = 1;
				current_index = right_index;
			}
		}else if(right_index != -1)
		{
			right_value = a[right_index];
			// update distance
			distance += right_distance;
			// mark visited
			already_visited[right_index] = 1;
			current_index = right_index;
		}
		else if(left_index != -1)
		{
			left_value_value = a[left_index];
			// update distance
			distance += left_distance;
			// mark visited
			already_visited[left_index] = 1;
			current_index = left_index;
		}
		else{
			printf("Hmmmm this should not be hit? \n");
		}

		// increment counter_limit
		counter_limit++;
	}

	/*
					END LOOP
	*/

	return distance;
}