include <bits/stdc++.h>

int h[n+1];
for (int i = 1; i <= n; i++) {
    cin >> h[i];
}

vector<int> dp(n+1, 0);
dp[1] = 0;

for (int i = 2; i <= n; i++) {
    if (i == 2) {
        dp[i] = abs(h[i] - h[i-1]);
    } else {
        dp[i] = min(dp[i-1] + abs(h[i] - h[i-1]), dp[i-2] + abs(h[i] - h[i-2]));
    }
}

cout << dp[n];

return 0;