#include<bits/stdc++.h>
using namespace std;
#define int long long
int a[114514];
signed main(){
    int n,c,b;
    cin>>n>>c>>b;
    int sum=0;
    for(int j=0;j<n;j++){
        cin>>a[j];
    }
    for(int i=0;i<n-1;i++){
        sum+=min((a[i+1]-a[i])*c,b);
    }
    cout<<sum<<endl;
}