#include <bits/stdc++.h>
#include <string.h>
using namespace std;
#define ll long long
 
void solve(){
 ll n,x,y;cin>>n>>x>>y;
 string a,b;cin>>a>>b;map<char,int>mp;
 for(auto p:a){mp[p]++;}
 ll ans=0;
 for(ll i=0;i<n;i++){int p=0;
     if(a[i]==b[i]){p=1;}
     if(a[i]!=b[i]){
         if(mp[b[i]]==0 || x>=2*y){ans+=y;mp[a[i]]--;p=1;}
         else{for(int j=i+1;j<n;j++){if((a[j]==b[i]) && (a[i]==b[j])){ans+=x;mp[a[j]]--;mp[a[i]]--;a[j]=b[j];p=1;break;}}}
         if(p==0){ans+=y;}
     }
 }cout<<ans<<endl;
}
 
int main() {
   ios_base::sync_with_stdio(false);
   cin.tie(NULL);
   cout.tie(NULL);
   int t;cin>>t;
   while(t--)
   solve();
	return 0;
}