Construct a array using following rules


Consider there is a array $ a$ of length $ n$ , $ a=[a_i ,0 \leq i \leq n]$ and all $ a_i>0$ and I need to construct a array $ b$ of length $ n$ (if possible) , $ b=[b_i , 0\leq i \leq n]$ .Rules for making array b is all $ 1\leq b_i\leq 5$ .

Consider $ j=i+1$ ,if $ a_j>a_i$ then $ b_j>b_i$ ,if $ a_j<a_i$ then $ b_j<b_i$ and if $ a_i=a_j$ then $ b_i \neq b_j$ .

Example : $ a=[2,3,4]$ then $ b$ can be $ [1,2,3]$ ,any $ b$ is $ accepted$ .

My approach is to use a simple $ dynamic$ $ programming$ ,$ dp[i][j]$ where i will check if first $ i$ elements of $ b$ can be formed if $ b_i=j$ where $ 0<j<6$ if it is possible $ dp[i][j]=1$ else ,$ dp[i][j]=0$ .By this method i could find if answer exits but i could not find the array $ b$ ,I know array $ b$ can be formed by depth first search as we can see states are connected by i have no idea after that.Could anyone help me how to use dfs on this question.

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