贪心，二分

同类型题：蓝桥杯 算法提高 ADV-1175 打包

def judge(x):
    wood = 0
    max_val = 0
    ans_len = 0
    for i in ll:
        if i > x:
            return False
        elif max(max_val, i) * (ans_len + 1) <= x:
            max_val = max(max_val, i)
            ans_len += 1
        else:
            wood += 1
            max_val = i
            ans_len = 1
    if ans_len:
        wood += 1
    return wood <= m


n, m = map(int, input().split())
ll = list(map(int, input().split()))
l, r = 0, max(ll) * len(ll)
while l < r:
    mid = (l + r) // 2
    if judge(mid):
        r = mid
    else:
        l = mid + 1
print(l)

函数遍历中加入了一个剪枝，判断当单个画大于木板时直接返回false，否则代码会直接判断加入新元素后的大小