#include<bits/stdc++.h>
#pragma GCC optimize("O3")
#define ll long long
#define SNSNMO 100010
using namespace std;

ll n,k,p,ans;
ll a[SNSNMO];

int main()
{
	freopen("defeat.in","r",stdin);
	freopen("defeat.out","w",stdout);
    ios::sync_with_stdio(false);
    cin.tie(nullptr);cout.tie(nullptr);
    cin>>n>>k>>p;
    for(int i=1;i<=n;++i)
    {
        cin>>a[i];
    }
    if(p==0)
    {
        for(int i=n;i>1;--i)
        {
            ans+=abs(a[i]-a[i-1]);
        }
        ans+=abs(a[1]-k);
        cout<<ans;
    }
    return 0;
}