B - Frog 2.cpp

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define mod 1000000007
#define Time cerr << "time taken : " << (float)clock() / CLOCKS_PER_SEC << " secs" << endl;
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define vi vector<int>
#define onesbits(x) __builtin_popcountll(x)
#define zerobits(x) __builtin_ctzll(x)
#define sp(x, y) fixed << setprecision(y) << x
#define w(x)  \
    int x;    \
    cin >> x; \
    while (x--)
#define tk(x) \
    int x;    \
    cin >> x;
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#ifndef ONLINE_JUDGE
#define debug(x)       \
    cerr << #x << " "; \
    _print(x);         \
    cerr << endl;
#else
#define debug(x)
#endif
template <class T>
void _print(T t)
{
    cerr << t;
}
template <class T, class V>
void _print(pair<T, V> p)
{
    cerr << "{";
    _print(p.ff);
    cerr << ",";
    _print(p.ss);
    cerr << "}";
}
template <class T>
void _print(vector<T> v)
{
    cerr << "[ ";
    for (T i : v)
    {
        _print(i);
        cerr << " ";
    }
    cerr << "]";
}
template <class T>
void _print(vector<vector<T>> v)
{
    cerr << "[\n";
    for (int l = 0; l < v.size(); l++)
    {
        {
            for (int k = 0; k < v[l].size(); k++)
                cerr << v[l][k] << " ";
        }
        cerr << "\n";
    }
    cerr << "]";
}
template <class T, class V>
void _print(map<T, V> v)
{
    cerr << "[ ";
    for (auto i : v)
    {
        _print(i);
        cerr << " ";
    }
    cerr << "]";
}
template <class T>
void _print(set<T> v)
{
    cerr << "[ ";
    for (T i : v)
    {
        _print(i);
        cerr << " ";
    }
    cerr << "]";
}

const long long inf = 1e18;
const int MOD = 1 << 15;

bool isValid(string s)
{
    int len = s.size();
    for (int i = 0; i < len / 2; i++)
    {
        if (s[i] != s[len - 1 - i])
            return false;
    }
    return true;
}

int solveUtil(int n, vector<int>& height, vector<int>& dp, int k){
    dp[0]=0;
    for(int i=1;i<n;i++){
        int mmSteps = INT_MAX;
        
        for(int j=1;j<=k;j++){
            if(i-j>=0){
                int jump = dp[i-j]+ abs(height[i]- height[i-j]);
                mmSteps= min(jump, mmSteps);
            }
        }
        dp[i]= mmSteps;
    }
    return dp[n-1];
}

int solve(int n, vector<int>& height , int k){
    vector<int> dp(n,-1);
    return solveUtil(n, height, dp, k);
}

int32_t main() {
    fast

    int n,k;cin>>n>>k;

    vector<int> v(n);
    vector<int> dp(n,-1);

    for (int i = 0; i <n; i++){
      cin>>v[i];
    }

    cout<<solve(n,v,k)<<endl;
    
    return 0;
}