#include<cstdio>
#define LL long long
using namespace std;

const int NMAX = 16009;
LL sum;
LL n, k, v[16 * 1024];

inline int count(LL val)
{
    LL s = val, kk = k, i;
    for(i = 1; i <= n && kk; ++i)
        if(v[i] <= s) s-= v[i];
        else --kk, i--, s = val;

    if(i == n + 1) return 1;

    return 0;
}
inline LL caut(LL st, LL dr)
{
    LL m;
    while(st < dr)
    {
        m = (st + dr) >> 1;
        if(count(m)) dr = m;
        else st = m + 1;
    }
    return m;
}
int main()
{
    freopen("transport.in", "rt", stdin);
    freopen("transport.out", "wt", stdout);

    scanf("%ld%ld", &n, &k);
    for(LL i = 1; i <= n; ++i) scanf("%ld", &v[i]), sum += v[i];

    printf("%ld\n", caut(1, sum + sum));
    return 0;
}