#include<cstdio>
typedef long long ll;
ll min(ll x,ll y) {return x>y?y:x;}
int main()
{
	int n,a,b,x,y;
	ll ans=0;
	scanf("%d%d%d",&n,&a,&b);
	scanf("%d",&x);n--;
	while(n--)
	{
		scanf("%d",&y);
		ans+=min((ll)(y-x)*a,b);
		x=y;
	}
	printf("%lld\n",ans);
	return 0;
}