#include<iostream>

#include<cstring>

#include<cmath>

#include<algorithm>

#include<cstdio>

#include<vector>

using namespace std;

const int maxn=+;

int n,a[maxn];

int main()

{

    scanf("%d",&n);

    for(int i=;i<=n;i++) scanf("%d",&a[i]);

    a[]=;

    int ans=;

    for(int i=;i<=n;i++)

    {

        if(a[i]>a[i-]) ans=ans+(a[i]-a[i-])*,ans=ans+;

        else if(a[i]<a[i-]) ans=ans+(a[i-]-a[i])*,ans=ans+;

        else ans=ans+;

    }

    printf("%d\n",ans);

    return ;

}