Numberphile sequences

1221.c

// The Kolakoski Sequence
// https://youtu.be/co5sOgZ3XcM

#include <stdio.h>

#define MAX 99

int main()
{
	unsigned int seq[MAX];
	seq[0] = 1;
	seq[1] = 2;

	int i = 2;
	int s = 1;
	int a = 2;
	for (i = 1, s = 1; i < MAX; s++) {
		int j = seq[s];
		for (j = seq[s]; j != 0; j--) {
			seq[i] = a;
			i++;
			if (i == MAX) {
				break;
			}
		}
		(a == 1) ? (a = 2) : (a = 1);
	}

	for (i = 0; i < MAX; i++) {
		printf("%d", seq[i]);
	}
	printf("\n");

	return 0;
}

highly_composite_number.cpp

// 5040 and other Anti-Prime Numbers
// https://youtu.be/2JM2oImb9Qg

#include <iostream>
#include <cstdlib>
#include <map>

using namespace std;

int main(int argc, char* argv[])
{
	int max_num = 12;
	
	if (argc == 2) {
		max_num = atoi(argv[1]);
	}

	map<int, map<int,int> > numbers;
	int number = 1;
	map<int, int> factors;
	int prime = 0;

	number = 1;
	prime = 1;
	
	factors[prime] = 1;
	numbers[number] = factors;

	for (number = 2; number <= max_num; number++) {
		factors.clear();

		int n = number;
		for (prime = 2; prime <= n; prime++) {
			factors[prime] = 0;
			while (n % prime == 0) {
				n = n/prime;
				factors[prime]++;
			}
		}

		numbers[number] = factors;
	}

	for (int i = 1; i <= max_num; i++) {
		cout << i << ": ";
		int sum = 1;
		if (i != 1) {
			for (int p = 1; p <= max_num; p++) {
				if (numbers[i][p] != 0) {
					sum *= (numbers[i][p]+1);
				}
			}
		}
		cout << sum << endl;
	}

	return 0;
}