1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
#include "bits/stdc++.h" // Tomasz Nowak
using namespace std;     // University of Warsaw
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())
template<class A, class B> auto& operator<<(ostream &o, pair<A, B> p) {
	return o << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
	o << '{'; int i = 0; for(auto e : x) o << (", ")+2*!i++ << e; return o << '}';
}
#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n'
#else
#define debug(...) {}
#endif

string multiply(LL n, string s) {
	if(n == 0 or s.empty())
		return "";
	if(n == 1)
		return s;
	if(n < 10 and ssize(s) == 1)
		return to_string(n) + s;
	if(n < 10)
		return to_string(n) + "[" + s + "]";
	auto divide_by = [&](int d) {
		return multiply(d, multiply(n / d, s)) + multiply(n % d, s);
	};
	for(int d : {9, 8, 7, 6, 5, 4, 3, 2})
		if(n % d == 0)
			return divide_by(d);
	return divide_by(9);
}

string solve_without_borders(LL n) {
	if(n == 0)
		return "";
	if(n % 2 == 1)
		return solve_without_borders(n - 1) + multiply(n - 1, "E") + multiply(n - 1, "AC") + "A";

	assert(n % 2 == 0 and n > 0);
	LL rec = n / 2 - 1;
	return multiply(rec, "AE") 
		+ "A" 
		+ multiply(rec, "C") 
		+ multiply(2, solve_without_borders(rec)) 
		+ multiply(rec, "E") 
		+ multiply(rec, multiply(rec, "C") + multiply(rec, "EA") + "E")
		+ multiply(rec, "C")
		+ multiply(rec, "EA")
		+ "EAC"
		+ multiply(2 * rec, "AC")
		+ "A";
}

string solve(LL n) {
	return solve_without_borders(n) + multiply(n, "E") + multiply(n, "C");
}

int main() {
	cin.tie(0)->sync_with_stdio(0);

	LL n;
	cin >> n;
	string out = solve(n);
	cout << out.data() << '\n';
}