#include <iostream>
using namespace std;
void solve(int n, char start, char mid, char end){
if(n==1){
cout<<start<<" -> "<<end<<endl;
return;
}
solve(n-1, start, end, mid);
cout<<start<<" -> "<<end<<endl;
solve(n-1, mid, start, end);
}
int main() {
int n=3;
solve(n, 'A', 'B', 'C');
return 0;
}
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