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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(1); 
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

typedef pair<ll,ll> PLL;

const ll M1=1e9,M2=1e5;
int T;
int vis[M2*2],dp[M2*2];
string gao(ll x,string t) {
	if (x==0) return "";
	if (x==1) return t;
	if (x<=9) {
		if (SZ(t)==1) return to_string(x)+t;
		else return to_string(x)+"["+t+"]";
	} else {
		function<int(ll)> compopt=[&](ll y) {
			int id=y<=M2?y:M2+x/y;
			if (vis[id]==T) return dp[id];
			vis[id]=T;
			if (y==0) return dp[id]=0;
			if (y==1) return dp[id]=SZ(t);
			if (y<=9) return dp[id]=(SZ(t)==1)?2:3+SZ(t);
			dp[id]=1<<30;
			for (int i=9;i>=2;i--) {
				dp[id]=min(dp[id],3+compopt(y/i)+compopt(y%i));
				if (y/i==1&&SZ(t)==1) dp[id]=min(dp[id],2+compopt(y%i));
			}
			return dp[id];
		};
		function<string(ll)> constopt=[&](ll y) {
			int id=y<=M2?y:M2+x/y;
			if (y==0) return string();
			if (y==1) return t;
			if (y<=9) return (SZ(t)==1)?to_string(y)+t:to_string(y)+"["+t+"]";
			for (int i=9;i>=2;i--) {
				if (dp[id]==3+compopt(y/i)+compopt(y%i)) {
					return to_string(i)+"["+constopt(y/i)+"]"+constopt(y%i);
				}
				if (y/i==1&&SZ(t)==1&&dp[id]==2+compopt(y%i)) {
					return to_string(i)+t+constopt(y%i);
				}
			}
			assert(0);
			return string();
		};
		if (x<=M1) {
			++T;
			compopt(x);
			return constopt(x);
		}
		for (int i=9;i>=4;i--) if (x%i==0) {
			return gao(i,gao(x/i,t));
		}
		return gao(9,gao(x/9,t))+gao(x%9,t);
	}
}
string gopt(ll dx,ll dy) {
	assert(dx==0||dy==0||dx+dy==0);
	if (dx==0) {
		if (dy>0) return gao(dy,"F"); 
		else return gao(-dy,"C");
	} else if (dy==0) {
		if (dx>0) return gao(dx,"A");
		else return gao(-dx,"D");
	} else if (dx+dy==0) {
		if (dx>0) return gao(dx,"B");
		else return gao(dy,"E");
	}
	assert(0);
	return "";
}

int cc=0;
pair<string,vector<PLL>> build(ll n) {
	if (n==1) {
		return mp("A",vector<PLL>{mp(0,0),mp(0,1),mp(1,0)});
	} else if (n==2) {
		return mp("AFDBA",vector<PLL>{mp(0,0),mp(0,2),mp(2,0)});
	} else if (n%2==1) {
		auto [op2,pt2]=build(n-1);
		op2+="E";
		op2+=gao(n-2,"FD");
		op2+="F";
		op2+=gao(n-1,"B");
		op2+="C";
		op2+="A";
		pt2.pop_back();
		pt2.push_back(mp(n-2,1));
		pt2.pb(mp(n-1,1));
		pt2.pb(mp(n,0));
		return mp(op2,pt2);
	} else {
		auto [op2,pt2]=build(n/2);
		op2=gao(2,op2);
		per(i,1,SZ(pt2)) {
			op2+=gopt(pt2[i-1].fi-pt2[i].fi,pt2[i-1].se-pt2[i].se);
		}
		op2+="E";
		op2+=gao(n/2,"AE");
		op2+=gao(n/2-1,gao(n/2-1,"DB")+"D"+gao(n/2,"F"));
		cc+=SZ(gao(n/2-1,gao(n/2-1,"DB")+"D"+gao(n/2,"F")));
		pt2.pop_back();
		pt2.push_back(mp(n/2-1,1));		
		pt2.push_back(mp(n/2-1,n/2+1));
		pt2.push_back(mp(0,n));
		for (auto &[x,y]:pt2) swap(x,y);
		for (auto &c:op2) if (c>='A'&&c<='F') c='A'+'F'-c;
		return mp(op2,pt2);
	}
}

int main() {
	ll n;
	scanf("%lld",&n);
	auto [op2,pt2]=build(n);
	per(i,1,SZ(pt2)) {
		op2+=gopt(pt2[i-1].fi-pt2[i].fi,pt2[i-1].se-pt2[i].se);
	}
	printf("%s\n",op2.c_str());
	//fprintf(stderr,"tot %d cc %d\n",SZ(op2),cc);
}