#include<iostream> using namespace std; void h(int n,char a,char b,char c) { if(n==0) return ; h(n-1,a,c,b); printf("%c->%d->%c\n",a,n,b); printf("%c->%d->%c\n",a,n,b); h(n-1,a,b,c); } int main() { int n; char a,b,c; cin>>n>>a>>b>>c; h(n,a,b,c); return 0; }