#include<bits/stdc++.h>
using namespace std;
#define MAXN 100005
int a[MAXN],diff[MAXN],n,k,p;
int main(){
    freopen("defeat.in","r",stdin);
    freopen("defeat.out","w",stdout);
    scanf("%d %d %d",&n,&k,&p);
    for(int i=1;i<=n;++i){
        scanf("%d ",&a[i]);
        diff[i] = a[i]-a[i-1];
    }
    if(p==0){
        long long ans=0;
        ans += abs(k-a[1]);
        for(int i=2;i<=n;++i){
            ans+= abs(diff[i]);
        }
        printf("%lld",ans);
    }
    else{
        printf("我不会！");
    }
    return 0;
}