How to solve this problem?

Hello everyone,↵
I wrote down a problem statement in class because I was bored. Sadly, I didn't figure out its solution.↵
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Problem: ↵
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Walid was assigned to build a network, however the required network is unique in it's own sense.↵
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The assigned network consists of 2 types of nodes: Group Owners and Slaves.↵
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Each group consists of a group owner and at most d slaves.↵
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Note: You can't have a group inside a group.↵
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Each second, r nodes will join the network. There will be a total of m insertions.↵
A node can either declare itself as a group owner, or join an existing network if possible.↵
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However, ~~creating a GO costs~~for a node to declare itself as a group owner, there will be an overhead of ~~weigh~~cost d, while joining an existing network costs an overhead of weight 1.↵
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At time 0, the network is empty.↵
Walid task is to create ~~the~~a network with minimum ~~weight possible~~overhead.↵
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Input:↵
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- n0 : Initial number of nodes-↵
- m  : Number of insertions↵
- r  : Number of nodes joining the network↵
- d  : Maximum number of slaves allowed per group↵
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Output:↵
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Print the ~~initial~~ number of groups ~~required~~at t = 1 to build a network with least cost at time m.↵
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I think this problem is a DP problem.↵
Any help?↵
Thanks!