Dynamic planning-The total number of sub-arrays multiplied by K Subarray product less Than k

2018-09-01 23:02:46

Problem solving:

Problem solving:

At the beginning, a glance at the past is a DP, save each number end of the length and, finally, the sum is good, as for the length of how to ask, the subject needs to use sliding window to maintain.

After writing the code, it is not necessary to actually apply for a 1000-length array to save each number, and simply sum it up.

    public int Numsubarrayproductlessthank (int[] nums, int k) {        int res = 0;        int begin = 0;        int cur = 1;        for (int end = 0; end < Nums.length; end++) {            cur *= nums[end];            while (Begin <= End && cur >= k) {                cur/= nums[begin];                begin++;            }            if (end < begin) Continue;            Res + = End-begin + 1;        }        return res;    }

Dynamic planning-The total number of sub-arrays multiplied by K Subarray product less Than k