sr=input().split()
n=int(sr[0])
m=int(sr[1])
a=[]
s=[0 for i in range(m)]
sr=input().split()
for i in range(n):
    a.append(int(sr[i]))
for i in range(m):
    s[i]=a[i]
for i in range(m,n):
    xiao=0
    for j in range(1,m):
        if(s[j]<s[xiao]):
            xiao=j
    s[xiao]=s[xiao]+a[i]
da=0
for i in range(1,m):
    if(s[i]>s[da]):
        da=i
print(s[da])
/**************************************************************
	Problem: 1485
	User: admin
	Language: Python
	Result: Accepted
	Time:963 ms
	Memory:35064 kb
****************************************************************/