The dynamic programming approach uses a dp array where dp[i] is true if there is a valid partition for the subarray nums[0..i]. We initialize dp[0] as false because there cannot be a valid partition for a single element. Then, for each i, we check for all valid configurations of subarrays ending at i, i.e., [i-1,i], [i-2,i], and [i-2,i-1,i], updating the dp array accordingly.

The greedy approach attempts to form valid subarrays by traversing the array and greedily picking the largest valid partition at each position. While processing the elements, if a valid subarray is found, the elements involved are ignored in subsequent iterations. Note, this provides a simple but possibly non-optimal solution for certain edge cases.