├── SimpleStorage.sol
└── StorageFactory.sol


/SimpleStorage.sol:
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 1 | // SPDX-License-Identifier: MIT
 2 | 
 3 | pragma solidity ^0.6.0;
 4 | 
 5 | contract SimpleStorage {
 6 |     
 7 |     // this will get initialized to 0!
 8 |     uint256 favoriteNumber;
 9 |     bool favoriteBool;
10 |     
11 |     struct People {
12 |         uint256 favoriteNumber;
13 |         string name;
14 |     }
15 |     
16 |     People[] public people;
17 |     mapping(string => uint256) public nameToFavoriteNumber;
18 |     
19 |     function store(uint256 _favoriteNumber) public {
20 |         favoriteNumber = _favoriteNumber;
21 |     }
22 |     
23 |     function retrieve() public view returns(uint256) {
24 |         return favoriteNumber;
25 |     }
26 |     
27 |     function addPerson(string memory _name, uint256 _favoriteNumber) public{
28 |         people.push(People(_favoriteNumber, _name));
29 |         nameToFavoriteNumber[_name] = _favoriteNumber;
30 |     }    
31 |     
32 | }
33 | 


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/StorageFactory.sol:
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 1 | // SPDX-License-Identifier: MIT
 2 | 
 3 | pragma solidity ^0.6.0;
 4 | 
 5 | import "./SimpleStorage.sol"; 
 6 | 
 7 | contract StorageFactory is SimpleStorage {
 8 |     
 9 |     SimpleStorage[] public simpleStorageArray;
10 |     
11 |     function createSimpleStorageContract() public {
12 |         SimpleStorage simpleStorage = new SimpleStorage();
13 |         simpleStorageArray.push(simpleStorage);
14 |     }
15 |     
16 |     function sfStore(uint256 _simpleStorageIndex, uint256 _simpleStorageNumber) public {
17 |         // Address 
18 |         // ABI 
19 |         //this line has an explicit cast to the address type and initializes a new SimpleStorage object from the address
20 |         SimpleStorage(address(simpleStorageArray[_simpleStorageIndex])).store(_simpleStorageNumber); 
21 | 
22 |         //this line simply gets the SimpleStorage object at the index _simpleStorageIndex in the array simpleStorageArray
23 |         //simpleStorageArray[_simpleStorageIndex].store(_simpleStorageNumber);
24 |     }
25 |     
26 |     function sfGet(uint256 _simpleStorageIndex) public view returns (uint256) {
27 |         //this line has an explicit cast to the address type and initializes a new SimpleStorage object from the address 
28 |         return SimpleStorage(address(simpleStorageArray[_simpleStorageIndex])).retrieve(); 
29 | 
30 |         //this line simply gets the SimpleStorage object at the index _simpleStorageIndex in the array simpleStorageArray
31 |         //return simpleStorageArray[_simpleStorageIndex].retrieve(); 
32 |     }
33 | }
34 | 


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