题解 | 空间跃迁

n,k=list(map(int,input().split()))
times=[0]+list(map(int,input().split()))
for i in range(1,n):
    times[i]=times[i]+times[i-1]
g=0
for j in range(n-k):
    middle=times[j+k]-times[j]
    if middle>g:
        g=middle
print(times[-1]-g)