#include<bits/stdc++.h>
using namespace std;
long long n,x,y,a[5010],b[5010],ct1=0,ct2=0;
long long ans=0;
string s;
int main(){
    freopen("zerone.in","r",stdin);
    freopen("zerone.out","w",stdout);
    cin>>n>>x>>y;
    cin>>s;
    for(int i=0;i<s.length();i++){
        if(s[i]=='0')a[i+1]=0;
        else a[i+1]=1,ct1++;
    }
    cin>>s;
    for(int i=0;i<s.length();i++){
        if(s[i]=='0')b[i+1]=0;
        else b[i+1]=1,ct2++;
    }
    if(ct1!=ct2){
        cout<<-1<<endl;
        return 0;
    }
    for(int i=1;i<=n;i++){
        if(a[i]!=b[i])ans+=y;
    }
    cout<<ans/2<<endl;
    return 0;
}