/*
    Programmer : Alexandru Olteanu
*/
#include<bits/stdc++.h>
using namespace std;
// GCC Optimizations
// #pragma GCC optimize("Ofast");
// #pragma GCC target("fma,sse,sse2,sse3,ssse3,sse4,popcnt")
// #pragma GCC target("abm,mmx,avx,avx2,tune=native")
// #pragma GCC optimize(3)
// #pragma GCC optimize("inline")
// #pragma GCC optimize("-fgcse")
// #pragma GCC optimize("-fgcse-lm")
// #pragma GCC optimize("-fipa-sra")
// #pragma GCC optimize("-ftree-pre")
// #pragma GCC optimize("-ftree-vrp")
// #pragma GCC optimize("-fpeephole2")
// #pragma GCC optimize("-ffast-math")
// #pragma GCC optimize("-fsched-spec")
// #pragma GCC optimize("unroll-loops")
// Useful
mt19937 rng((unsigned int) chrono::steady_clock::now().time_since_epoch().count());
#define FastEverything  ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define HighPrecision cout<<fixed<<setprecision(17);
typedef long long ll;
typedef pair<int,int> pii;
ll const mod=1000000007LL;
ll const mod2 = 100000000LL;
ll const md=998244353LL;
ll mypowr(ll a,ll b, ll mod1) {ll res=1;if(b<0)b=0;a%=mod1; assert(b>=0);
for(;b;b>>=1){if(b&1)res=res*a%mod1;a=a*a%mod1;}return res;}
ll mypow(ll a,ll b) {ll res=1;if(b<0)b=0;assert(b>=0);
for(;b;b>>=1){if(b&1)res=res*a;a=a*a;}return res;}
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(), x.rend()

ifstream in("transport.in");
ofstream out("transport.out");
#define cin in
#define cout out

const ll infll = 9e18;
const int inf = 2e9;
const ll maxn = 1e5 + 2;

int a[maxn], n, k;

bool check(int x) {
    int have = x;
    int t = 1;
    for (int i = 1; i <= n; ++i) {
        if (have >= a[i]) {
            have -= a[i];
        }
        else {
            ++t;
            have = x - a[i];
        }
    }
    if (t <= k)return 1;
    return 0;
}

int main()
{
    FastEverything
    HighPrecision

    int test = 1;
    // cin >> test;
    for (int tt = 1; tt <= test; ++tt) {
        cin >> n >> k;
        int maxi = -inf;
        for (int i = 1; i <= n; ++i) {
            cin >> a[i];
            maxi = max(maxi, a[i]);
        }
        int left = maxi, right = inf, answer = inf;
        while (left <= right) {
            int mid = left + (right - left) / 2;
            if (check(mid)) {
                answer = mid;
                right = mid - 1;
            }
            else {
                left = mid + 1;
            }
        }
        cout << answer << '\n';

    }


    return 0;
}