stablegradients/pie-gem5-pairs huggingface dataset:
// Slower C++ solution:
//#include <bits/stdc++.h>

#include <algorithm>

#include <iostream>

#include <iomanip>

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <cstring>

#include <vector>

#include <string>

#include <climits>

#include <map>

#include <set>

#include <stack>

#include <queue>

#include <deque>

#include <stdio.h>

//#define int long long

using namespace std;

#define loop(n) for(int i=0;i<n;i++)

#define endl '\n'

#define OnlineJudgec

#define F first

#define S second

#define  precision(n)  cout << fixed << setprecision(n)

#define clr(v,d ) memset(v, d, sizeof(v))

typedef long long ll;

typedef vector<int> vi;

void init()

{

    cin.tie(0);

    cin.sync_with_stdio(0);

    cout.tie(0);

    #ifdef OnlineJudge

    freopen("input.txt","r",stdin);

    freopen("output.txt","w",stdout);

    #endif

}

ll S(ll x){ll s = 0;while(x){s += x % 10;x /= 10;}return s;} /// sum of digits.

ll powe(ll a , ll n){if(n == 1)return a;return a * powe(a ,n-1);}

ll com(int n,int m){ll z = 1;for(int i = 0; i < m;i++){z = z * ( n - i) / (i + 1) ;}return z;}

int dx[] = {1,-1,0,0};

int dy[] = {0,0,1,-1};

int dr[] = {0,0,0,1,1,1,-1,-1,-1};

int dc[] ={-1,0,1,-1,0,1,-1,0,1};

/// <<------------------------------------------------------------------------------>>

const int mx = 100009;

int n;

int arr[mx];

int dp[mx];

int solve(int idx)

{

    if(idx == n-1)return 0;

    int &rst = dp[idx];

    if(~rst) return rst;

    int choice = 1e9 , choice2 = 1e9;

    if(idx + 1 < n)

        choice = solve(idx+1) + abs(arr[idx] - arr[idx + 1]);

    if(idx + 2 < n)

       choice2 = solve(idx+2) + abs(arr[idx] - arr[idx + 2]);

    return rst = min(choice , choice2);

}

/// <<------------------------------------------------------------------------------>>

int main()

{

    init();

    cin >> n;

    loop(n) cin >> arr[i];

    clr(dp,-1);

    cout<<solve(0);

}


// Faster C++ solution for the same problem (measured speedup: 1.3944438529966776x):
#include<bits/stdc++.h>

#include <vector>

#include <string>

#include <cmath>

#include <set>

#include <stdio.h>

#include <algorithm>

#include <map>

#include <queue>

#include <unordered_map>

#define ll long long

#define pii pair <int, int>

#define pll pair <long long, long long>

#define plxy pair <long long, pll>

#define INT_MAX 1e18

#define Keep_calm_You_are_still_learning ios_base::sync_with_stdio(false);cin.tie(NULL);

using namespace std;

using namespace std;

const int mod=1e9+7;

const int N=1e5+5;

ll dp[N];

int main()

{

    ll n,arr[N];

    cin>>n;

    for(ll i=0;i<n;i++)

        cin>>arr[i];

    dp[0]=0;

    dp[1]=abs(arr[1]-arr[0]);

    for(ll i=2;i<n;i++)

    {

        dp[i]=min(abs(arr[i]-arr[i-1])+dp[i-1],abs(arr[i]-arr[i-2])+dp[i-2]);

    }

    cout<<dp[n-1];

    return 0;

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

const int mx = 100005;

int dp[mx];

int A[mx];

void memo(int i,int n)

{

	if(i>n) return;

	dp[i] = min(dp[i-2]+abs(A[i-2]-A[i]),dp[i-1]+abs(A[i-1]-A[i]));

	memo(i+1,n);

}

int main()

{

     int n;cin>>n;

     for(int i=1;i<=n;i++)

     	cin>>A[i];

     memset(dp,0,sizeof(dp));

     dp[2] = abs(A[1]-A[2]);

     memo(3,n);

     cout<<dp[n]<<endl;

     return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.4032939918812264x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;



#define INF 1e18;

#define MAX_N 100005

long long N, h[MAX_N], memo[MAX_N];



long long dp(int pos) {

  if (pos < 1) {

  	return INF;

  }

  if (pos == 1) {

  	return 0;

  }

  if (pos == 2) {

  	return abs(h[2] - h[1]);

  }

  if (memo[pos] != -1) {

  	return memo[pos];

  }

  return memo[pos] = min(abs(h[pos] - h[pos - 1]) + dp(pos - 1), (abs(h[pos] - h[pos - 2]) + dp(pos - 2)));

}



int main() {

  cin >> N;

  for (int i = 1; i <= N; i++) {

  	cin >> h[i];

  }

  /*

  memo[2] = abs(h[2] - h[1]);

  for (int i = 3; i <= N; i++) {

  	memo[i] += min(abs(h[i] - h[i - 1]) + memo[i - 1], abs(h[i] - h[i - 2]) + memo[i - 2]);

  }

  */

  /*

  for (int i = 1; i <= N; i++) {

  	cout << i << ' ' << memo[i] << '\n';

  }

  */

  // cout << memo[N] << '\n';

  memset(memo, -1, sizeof memo);

  cout << dp(N) << '\n';

}

// Faster C++ solution for the same problem (measured speedup: 1.8038962994169383x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int n , a[1000000] , frog , memo[1000000];



int f(int n){

	if(n == 1)return 0;

	if(n == 2)return abs(a[1] - a[2]);

	if(memo[n] != -1)return memo[n];

	memo[n] = min(f(n-1) + abs(a[n] - a[n-1]) , f(n-2) + abs(a[n] - a[n-2]));

	return memo[n];

}

int main(){

	memset(memo , -1 , sizeof(memo));

	scanf("%d" , &n);

	for(int i = 1 ; i <= n ; i++){

		scanf("%d" , &a[i]);

	}

	printf("%d" , f(n));

}

// Faster C++ solution for the same problem (measured speedup: 5.083045079101667x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

#define eps 1e-3

#define pi acos(-1.0)

#define inf 0x3f3f3f3f

#define debug1 cout<<"&&";

#define debug2 cout<<"**";

#define pb push_back

#define ms(a, x) memset(a, x, sizeof(a))

#define forn(i, n) for(int i = 0; i < n; ++i)

#define for1(i, n) for(int i = 1; i <= n; ++i) 

typedef double db;

typedef long long ll;

typedef unsigned long long ull;

using namespace std;

const int mod = 1e9;

const int N = 1e5+10;

/*=======================================================================*/



int n, h[N], sum;

int f[N];



int main() {

   scanf("%d", &n);

   for1(i, n) {

      scanf("%d", &h[i]);

   }

   ms(f, inf);

   f[n] = 0;

   for(int i = n; i > 1; i--) {

      if(i == 2) {

         f[i-1] = min(f[i-1], f[i] + abs(h[i] - h[i-1]));

      } else {

         f[i-1] = min(f[i-1], f[i] + abs(h[i] - h[i-1]));

         f[i-2] = min(f[i-2], f[i] + abs(h[i] - h[i-2]));

      }

      // if(i == 2) {

      //    sum += abs(h[i] - h[1]);

      //    i--;

      // } else {

      //    if(abs(h[i] - h[i-1]) < abs(h[i] - h[i-2])) {

      //       sum += abs(h[i] - h[i-1]);

      //       i -= 1;

      //    } else {

      //       sum += abs(h[i] - h[i-2]);

      //       i -= 2;

      //    }

      // }

   }

   cout << f[1] << endl;

   return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.3940897077749865x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;



const int nax = 1e5+3;

int n;

int dp[nax];

int a[nax];

int f(int i){

	if (i==n-1) return 0;

	if(dp[i]!=-1) return dp[i];

	int ans = abs(a[i]-a[i+1])+f(i+1);

	if(i!=n-2) ans = min(ans, abs(a[i]-a[i+2])+f(i+2));

	return dp[i]=ans;

}

int main(){

	cin>>n;

	for(int i=0; i<n; i++) cin>>a[i];

	memset(dp, -1, sizeof dp);

	cout<<f(0)<<endl;

	return 0;

}


// Faster C++ solution for the same problem (measured speedup: 1.4032494906415618x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

typedef long long int lli;

typedef long double ld;

const int oo = 1e9;

const int mod = 1e9+9;



const int ppt = 1e5+3;

int n;

int dp[ppt];

int a[ppt];

int f(int i){

	if (i==n-1) return 0;

	if(dp[i]!=-1) return dp[i];

	int jpr = abs(a[i]-a[i+1])+f(i+1);

	if(i!=n-2) jpr = min(jpr, abs(a[i]-a[i+2])+f(i+2));

	return dp[i]=jpr;

}

int main(){

	cin>>n;

	for(int i=0; i<n; i++) cin>>a[i];

	memset(dp, -1, sizeof dp);

	cout<<f(0)<<endl;

	return 0;

}


// Faster C++ solution for the same problem (measured speedup: 1.4032494906415618x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

typedef long long int lli;

typedef long double ld;

const int oo = 1e9;

const int mod = 1e9+9;



const int nax = 1e5+3;

int n;

int dp[nax];

int a[nax];

int f(int i){

	if (i==n-1) return 0;

	if(dp[i]!=-1) return dp[i];

	int ans = abs(a[i]-a[i+1])+f(i+1);

	if(i!=n-2) ans = min(ans, abs(a[i]-a[i+2])+f(i+2));

	return dp[i]=ans;

}

int main(){

	cin>>n;

	for(int i=0; i<n; i++) cin>>a[i];

	memset(dp, -1, sizeof dp);

	cout<<f(0)<<endl;

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.4032494906415618x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

typedef long long int lli;

typedef long double ld;

const int oo = 1e9;

const int mod = 1e9+9;

/*ll gcd(ll x, ll y){return (y ? gcd(y, x%y) : x); }

*ll lcm(ll x, ll y){return x*(y/gcd(x,y));}

*void exEuclid(int a, int b){

	if(b==0){x = 1; y=0; d=a; return ;}

	exEuclid(b, a%b);

	int x1=y;

	int y1=x-(a/b)*y;

	x=x1;

	y=y1;

} 

* */

//===========================================================//

const int nax = 1e5+3;

int n;

int dp[nax];

int a[nax];

int f(int i){

	if (i==n-1) return 0;

	if(dp[i]!=-1) return dp[i];

	int ans = abs(a[i]-a[i+1])+f(i+1);

	if(i!=n-2) ans = min(ans, abs(a[i]-a[i+2])+f(i+2));

	return dp[i]=ans;

}

int main(){

	cin>>n;

	for(int i=0; i<n; i++) cin>>a[i];

	memset(dp, -1, sizeof dp);

	cout<<f(0)<<endl;

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.4032257756692994x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

#define ll long long

ll dp[100009];

ll n,x;

vector<ll>v;

ll frog(ll pos)

{

    if(pos<=0)

        return 0;

    if(pos==1)

        return abs(v[0]-v[1]);

        if(dp[pos]==-1)

        {

            dp[pos]= min(abs(v[pos]-v[pos-1])+frog(pos-1),abs(v[pos]-v[pos-2])+frog(pos-2));

        }

    return dp[pos];

}



int main()

{

    cin>>n;

    memset(dp,-1,sizeof(dp));

    for(ll i=0; i<n; i++)

    {

        cin>>x;

        v.push_back(x);

    }

    cout<<frog(n-1)<<endl;

}


// Faster C++ solution for the same problem (measured speedup: 1.809293461015785x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>



using namespace std;

int v[1000010];

int memo[1000010];

int c;



int f(int i)

{



    if(memo[i]!=-1)

        return memo[i];



    if(i == 0)

        return memo[0] = 0;



    if(i == 1)

        return memo[1] = abs(v[0] - v[1]);



    return memo[i] = min(abs(v[i] - v[i-1]) + f(i-1), abs(v[i] - v[i-2]) + f(i-2));

}



int main()

{



    memset(memo, -1, sizeof(memo));

    cin>>c;



    for(int i = 0; i<c; i++)

    {

        cin>>v[i];

    }



    cout<<f(c-1)<<endl;



    return 0;

}

// Faster C++ solution for the same problem (measured speedup: 5.099629575632631x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

int h[100001];

int dp[100001];

int n;

int solve(int stone)

{

    if(stone+1==n) return dp[stone]=abs(h[stone]-h[stone+1]);

    if(stone+2==n) return dp[stone+2]=abs(h[stone]-h[stone+2]);

    if(dp[stone]!=-1) return dp[stone];

    return dp[stone]=min(abs(h[stone]-h[stone+1])+solve(stone+1),abs(h[stone]-h[stone+2])+solve(stone+2));

}



int main()

{

    int i;

    scanf("%d",&n);



    for(i=1; i<=n; i++)

        scanf("%d",&h[i]);



    memset(dp,-1,sizeof(dp));

    printf("%d\n",solve(1));





    return 0;

}


// Faster C++ solution for the same problem (measured speedup: 1.390938660917375x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include <bits/stdc++.h>



using namespace std;



int n, h[100002], dp[100002];



int sol(int i){

    if(i==n-1) return 0;

    if(i>=n) return 1E9;



    int &ret = dp[i];

    if(~ret) return ret;



    return ret = min(abs(h[i+1]-h[i]) + sol(i+1),

                     abs(h[i+2]-h[i]) + sol(i+2));

}



int main()

{

    cin >> n;

    for(int i=0; i<n; i++)

        cin >> h[i];



    memset(dp, -1, sizeof dp);

    cout << sol(0);

}


// Faster C++ solution for the same problem (measured speedup: 1.4014473600200814x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
//#include <bits/stdc++.h>

#include <algorithm>

#include <iostream>

#include <iomanip>

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <cstring>

#include <vector>

#include <string>

#include <climits>

#include <map>

#include <set>

#include <stack>

#include <queue>

#include <deque>

#include <stdio.h>

//#define int long long

using namespace std;

#define loop(n) for(int i=0;i<n;i++)

#define endl '\n'

#define OnlineJudgec

#define F first

#define S second

#define  precision(n)  cout << fixed << setprecision(n)

#define clr(v,d ) memset(v, d, sizeof(v))

typedef long long ll;

typedef vector<int> vi;

void init()

{

    cin.tie(0);

    cin.sync_with_stdio(0);

    cout.tie(0);

    #ifdef OnlineJudge

    freopen("input.txt","r",stdin);

    freopen("output.txt","w",stdout);

    #endif

}

ll S(ll x){ll s = 0;while(x){s += x % 10;x /= 10;}return s;} /// sum of digits.

ll powe(ll a , ll n){if(n == 1)return a;return a * powe(a ,n-1);}

ll com(int n,int m){ll z = 1;for(int i = 0; i < m;i++){z = z * ( n - i) / (i + 1) ;}return z;}

int dx[] = {1,-1,0,0};

int dy[] = {0,0,1,-1};

int dr[] = {0,0,0,1,1,1,-1,-1,-1};

int dc[] ={-1,0,1,-1,0,1,-1,0,1};

/// <<------------------------------------------------------------------------------>>

const int mx = 100009;

int n;

int arr[mx];

int dp[mx];

int solve(int idx)

{

    if(idx == n-1)return 0;

    int &rst = dp[idx];

    if(~rst) return rst;

    int choice = 1e9 , choice2 = 1e9;

    if(idx + 1 < n)

        choice = solve(idx+1) + abs(arr[idx] - arr[idx + 1]);

    if(idx + 2 < n)

       choice2 = solve(idx+2) + abs(arr[idx] - arr[idx + 2]);

    return rst = min(choice , choice2);

}

/// <<------------------------------------------------------------------------------>>

int main()

{

    init();

    cin >> n;

    loop(n) cin >> arr[i];

    clr(dp,-1);

    cout<<solve(0);

}


// Faster C++ solution for the same problem (measured speedup: 1.4155419971176x):
#include <bits/stdc++.h>

using namespace std;

int main()

{

    int n;

    cin>>n;

    int arr[n];

    long long dp[n];

   for(int i=0;i<n;i++)

   {

        cin>>arr[i];

   }

   dp[0]=0;

   dp[1]=abs(arr[1]-arr[0]);

   for(int i=2;i<n;i++)

   {

       dp[i]=min(dp[i-1]+abs(arr[i-1]-arr[i]),dp[i-2]+abs(arr[i-2]-arr[i]));

   }

   cout<<dp[n-1];

   return 0;

}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

const int mx = 100005;

int dp[mx];

int A[mx];

void memo(int i,int n)

{

	if(i>n) return;

	dp[i] = min(dp[i-2]+abs(A[i-2]-A[i]),dp[i-1]+abs(A[i-1]-A[i]));

	memo(i+1,n);

}

int main()

{

     int n;cin>>n;

     for(int i=1;i<=n;i++)

     	cin>>A[i];

     memset(dp,0,sizeof(dp));

     dp[2] = abs(A[1]-A[2]);

     memo(3,n);

     cout<<dp[n]<<endl;

     return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.3809771503848887x):
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define fast ios_base::sync_with_stdio(false),cin.tie(NULL)

#define x first

#define y second





int main() {

    fast;

    int n;

    cin>>n;

    vector<int> arr(n);

    for (int i = 0; i < n; ++i) {

        cin>>arr[i];

    }

    vector<int> dp(n);

    dp[0] = 0;

    dp[1] = abs(arr[0] - arr[1]);

    for (int i = 2; i < n; ++i) {

        dp[i] = min(abs(arr[i-1] - arr[i]) + dp[i-1], abs(arr[i-2] - arr[i]) + dp[i-2]);

    }

    cout<<dp[n-1];

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;



#define INF 1e18;

#define MAX_N 100005

long long N, h[MAX_N], memo[MAX_N];



long long dp(int pos) {

  if (pos < 1) {

  	return INF;

  }

  if (pos == 1) {

  	return 0;

  }

  if (pos == 2) {

  	return abs(h[2] - h[1]);

  }

  if (memo[pos] != -1) {

  	return memo[pos];

  }

  return memo[pos] = min(abs(h[pos] - h[pos - 1]) + dp(pos - 1), (abs(h[pos] - h[pos - 2]) + dp(pos - 2)));

}



int main() {

  cin >> N;

  for (int i = 1; i <= N; i++) {

  	cin >> h[i];

  }

  /*

  memo[2] = abs(h[2] - h[1]);

  for (int i = 3; i <= N; i++) {

  	memo[i] += min(abs(h[i] - h[i - 1]) + memo[i - 1], abs(h[i] - h[i - 2]) + memo[i - 2]);

  }

  */

  /*

  for (int i = 1; i <= N; i++) {

  	cout << i << ' ' << memo[i] << '\n';

  }

  */

  // cout << memo[N] << '\n';

  memset(memo, -1, sizeof memo);

  cout << dp(N) << '\n';

}

// Faster C++ solution for the same problem (measured speedup: 1.7752086060163916x):
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define fast ios_base::sync_with_stdio(false),cin.tie(NULL)

#define x first

#define y second





int main() {

    fast;

    int n;

    cin>>n;

    vector<int> arr(n);

    for (int i = 0; i < n; ++i) {

        cin>>arr[i];

    }

    vector<int> dp(n);

    dp[0] = 0;

    dp[1] = abs(arr[0] - arr[1]);

    for (int i = 2; i < n; ++i) {

        dp[i] = min(abs(arr[i-1] - arr[i]) + dp[i-1], abs(arr[i-2] - arr[i]) + dp[i-2]);

    }

    cout<<dp[n-1];

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

int n , a[1000000] , frog , memo[1000000];



int f(int n){

	if(n == 1)return 0;

	if(n == 2)return abs(a[1] - a[2]);

	if(memo[n] != -1)return memo[n];

	memo[n] = min(f(n-1) + abs(a[n] - a[n-1]) , f(n-2) + abs(a[n] - a[n-2]));

	return memo[n];

}

int main(){

	memset(memo , -1 , sizeof(memo));

	scanf("%d" , &n);

	for(int i = 1 ; i <= n ; i++){

		scanf("%d" , &a[i]);

	}

	printf("%d" , f(n));

}

// Faster C++ solution for the same problem (measured speedup: 5.002208481777553x):
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define fast ios_base::sync_with_stdio(false),cin.tie(NULL)

#define x first

#define y second





int main() {

    fast;

    int n;

    cin>>n;

    vector<int> arr(n);

    for (int i = 0; i < n; ++i) {

        cin>>arr[i];

    }

    vector<int> dp(n);

    dp[0] = 0;

    dp[1] = abs(arr[0] - arr[1]);

    for (int i = 2; i < n; ++i) {

        dp[i] = min(abs(arr[i-1] - arr[i]) + dp[i-1], abs(arr[i-2] - arr[i]) + dp[i-2]);

    }

    cout<<dp[n-1];

}
// Slower C++ solution:
#include <bits/stdc++.h>

#define eps 1e-3

#define pi acos(-1.0)

#define inf 0x3f3f3f3f

#define debug1 cout<<"&&";

#define debug2 cout<<"**";

#define pb push_back

#define ms(a, x) memset(a, x, sizeof(a))

#define forn(i, n) for(int i = 0; i < n; ++i)

#define for1(i, n) for(int i = 1; i <= n; ++i) 

typedef double db;

typedef long long ll;

typedef unsigned long long ull;

using namespace std;

const int mod = 1e9;

const int N = 1e5+10;

/*=======================================================================*/



int n, h[N], sum;

int f[N];



int main() {

   scanf("%d", &n);

   for1(i, n) {

      scanf("%d", &h[i]);

   }

   ms(f, inf);

   f[n] = 0;

   for(int i = n; i > 1; i--) {

      if(i == 2) {

         f[i-1] = min(f[i-1], f[i] + abs(h[i] - h[i-1]));

      } else {

         f[i-1] = min(f[i-1], f[i] + abs(h[i] - h[i-1]));

         f[i-2] = min(f[i-2], f[i] + abs(h[i] - h[i-2]));

      }

      // if(i == 2) {

      //    sum += abs(h[i] - h[1]);

      //    i--;

      // } else {

      //    if(abs(h[i] - h[i-1]) < abs(h[i] - h[i-2])) {

      //       sum += abs(h[i] - h[i-1]);

      //       i -= 1;

      //    } else {

      //       sum += abs(h[i] - h[i-2]);

      //       i -= 2;

      //    }

      // }

   }

   cout << f[1] << endl;

   return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.3719192436954089x):
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define fast ios_base::sync_with_stdio(false),cin.tie(NULL)

#define x first

#define y second





int main() {

    fast;

    int n;

    cin>>n;

    vector<int> arr(n);

    for (int i = 0; i < n; ++i) {

        cin>>arr[i];

    }

    vector<int> dp(n);

    dp[0] = 0;

    dp[1] = abs(arr[0] - arr[1]);

    for (int i = 2; i < n; ++i) {

        dp[i] = min(abs(arr[i-1] - arr[i]) + dp[i-1], abs(arr[i-2] - arr[i]) + dp[i-2]);

    }

    cout<<dp[n-1];

}