func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long MAXN = 1e5 + 1, INF = 1e17, MOD = 1e9 + 7;   long long n;   string s, t =  UDRL ;   map<char, long long> m;   int32_t main() {     ios_base::sync_with_stdio(0);     cin >> n >> s;     for (long long i = 0; i < n; ++i) {       m[s[i]]++;     }     cout << 2 * (min(m[t[0]], m[t[1]]) + min(m[t[2]], m[t[3]])) << endl;     return 0;   }   