C++ :

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1e4 + 5;
int n;
map<string, string> m;
string s, ans;
signed main() {
    cin>>n;
    for(int i = 1; i <= n; i++) {
        string a, b;
        cin>>a>>b;
        m[a] = b;
    }
    cin>>s;
    s += '.';
    string t = "";
    for(char c : s) {
        if(c >= 'a' && c <= 'z') t += c;
        else {
            if(t != "") {
                if(m.count(t)) ans += m[t];
                else ans += "UNK";
                t = "";    
            }
            ans += c;
        }
        // cout<<c<<" "<<ans<<" "<<t<<endl;
    }
    ans.pop_back();
    cout<<ans<<endl;
    return 0;
}