#pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #include <bits/stdc++.h> using namespace std; #define pb push_back #define all(a) a.begin(),a.end() typedef long long ll; typedef pair<int,int> pii; typedef pair<ll,ll> pll; typedef unsigned long long ull; typedef vector<int> vi; void solve(){ int n,h; cin >> n >> h; priority_queue<ll> slope_left; priority_queue<ll,vector<ll>,greater<ll>> slope_right; ll off_left = 0, off_right = 0; ll ans = 0; int a; cin >> a; slope_left.push(a); slope_right.push(a); off_left = -h; off_right = h; for(int i = 1; i < n; i++){ cin >> a; ll low = a-off_left; ll up = a-off_right; if(low < slope_left.top()){ ans += slope_left.top() - low; slope_left.push(low); slope_left.push(low); ll b = slope_left.top(); slope_left.pop(); b += off_left; slope_right.push(b-off_right); }else if(up > slope_right.top()){ ans += up - slope_right.top(); slope_right.push(up); slope_right.push(up); ll b = slope_right.top(); slope_right.pop(); b += off_right; slope_left.push(b-off_left); }else{ slope_left.push(low); slope_right.push(up); } off_left += -h; off_right += h; } cout << ans; } signed main(){ cin.tie(0)->sync_with_stdio(0); int t = 1; // cin >> t; while(t--){solve();} }