Recommended way to split ERC20 initial token supply

[selv]

Initially all supplied token will be assigned to _totalSupply and _balances[owner]. Suppose I do not want to sell all token in public sale. I want to sell only 30% of token in public sale, 20% of token through organization A and 30% token through organization B. And I want to hold 20% token to give as incentives who holds the token long time. If I am following ERC20 and openZeppelin standard how to do these things. Is there any sample smart contract or any good tutorial.

[Skyge]

Sounds like a crowdsale contract, but not exactly. There is simple contract you can have a look:

Simple ERC20 Crowdsale

The following is an example of a simple ERC20 Crowdsale. The following code has not been tested nor audited. Seek appropriate advice on regulatory compliance and your solution should have appropriate testing and auditing Recommend reading: Points to consider when creating a fungible token (ERC20, ERC777) Setup Crowdsales are included in OpenZeppelin Contracts 2.x, they are not in OpenZeppelin Contracts 3.x. To install: npm install @openzeppelin/contracts@2.5.1 Documentation: htt…

And here is document: https://docs.openzeppelin.com/contracts/2.x/crowdsales

And for the distributions, maybe it could be

_mint(OrganizationA, _totalSupply*2/10);
_mint(OrganizationB, _totalSupply*3/10);
……