code如下，死循环不输出：

#include<bits/stdc++.h>
#define int long long
using namespace std;
int n;
string s1,s2;
int dist(string a,string b){
	for(int i=0;i<a.size();i++){
		if(a[i]!=b[i]){
			if(i==a.size()-1){
				return 1;
			}
			else{
				char ch;
				if(a[i]!='L'&&b[i]!='L'){
					ch='L';
				}
				if(a[i]!='T'&&b[i]!='T'){
					ch='T';
				}
				if(a[i]!='R'&&b[i]!='R'){
					ch='R';
				}
				string t1="",t2="",t3="",t4="";
				t1+=a[i],t2+=b[i],t3+=a[i],t4+=b[i];
				for(int j=1;j<a.size();j++){
					t1+=b[i];
					t2+=a[i];
					t3+=ch;
					t4+=ch;
				}
				return min(dist(a,t1)+dist(b,t2)+1,dist(a,t3)+dist(b,t4)+n);
			}
		}
	}
}
signed main(){
	cin>>n>>s1>>s2;
	cout<<dist(s1,s2);
	return 0;
}