#include <bits/stdc++.h>
using namespace std;
#define ll long long int
const int N = 1e5+7;
int arr[N];
int dp[N];
 
int f(int idx, int n){
	if(idx >= n){
		return 0;
	}
	if(dp[idx]!=-1) return dp[idx];
	int op1 = abs(arr[idx+1]-arr[idx])+f(idx+1, n);
	int op2 = abs(arr[idx+2]-arr[idx])+f(idx+2, n);
	return dp[idx]=min(op1,op2);
}
 
int main() {
	int n;
	cin>>n;
	for(int i=1; i<=n; i++){
		cin>>arr[i];
	}
	memset(dp, -1, sizeof(dp));
	cout<<f(1, n)<<endl;
	return 0;
}

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