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sourav maji

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I have wrote 5+ smart contracts for beginner web3 developer

If you’re a beginner Web3 developer, smart contracts are an excellent way to get started with blockchain development. Smart contracts are self-executing contracts that automatically execute when certain conditions are met. They are programmed to operate on the Ethereum blockchain and other similar blockchain platforms, and they allow developers to create decentralized applications (dApps) that operate autonomously and securely. In this article, we will discuss 5+ smart contract ideas for beginner Web3 developers, along with sample code.

1) Digital Token Smart Contract : A digital token smart contract is a basic smart contract that creates a digital asset that can be traded on the blockchain. This is an excellent way to learn the fundamentals of smart contract development, and it can be used as a base for more complex projects. The following code shows how to create a basic digital token smart contract:

pragma solidity ^0.8.0;

contract MyToken {
    string public name = "MyToken";
    string public symbol = "MT";
    uint256 public totalSupply = 1000000;
    mapping(address => uint256) public balances;

    constructor() {
        balances[msg.sender] = totalSupply;
    }

    function transfer(address _to, uint256 _amount) public returns (bool success) {
        require(balances[msg.sender] >= _amount);
        balances[msg.sender] -= _amount;
        balances[_to] += _amount;
        emit Transfer(msg.sender, _to, _amount);
        return true;
    }

    event Transfer(address indexed _from, address indexed _to, uint256 _amount);
}
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2.Voting Smart Contract : A voting smart contract is a more complex smart contract that can be used to conduct secure and transparent voting. This is an excellent way to learn how to create a smart contract that interacts with multiple parties. The following code shows how to create a basic voting smart contract

pragma solidity ^0.8.0;

contract Voting {
    mapping(bytes32 => uint256) public votes;

    function vote(bytes32 candidate) public {
        require(votes[candidate] >= 0);
        votes[candidate] += 1;
    }

    function getVotes(bytes32 candidate) public view returns (uint256) {
        return votes[candidate];
    }
}
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3.Lottery Smart Contract : A lottery smart contract is a smart contract that can be used to create a decentralized lottery. This is an excellent way to learn how to create a smart contract that interacts with random numbers. The following code shows how to create a basic lottery smart contract:

pragma solidity ^0.8.0;

contract Lottery {
    address payable[] public players;

    function play() public payable {
        require(msg.value == 1 ether);
        players.push(payable(msg.sender));
    }

    function generateRandomNumber() private view returns (uint256) {
        return uint256(keccak256(abi.encodePacked(block.timestamp, block.difficulty))) % players.length;
    }

    function distributePrize() public {
        require(players.length > 0);
        uint256 winnerIndex = generateRandomNumber();
        players[winnerIndex].transfer(address(this).balance);
        players = new address payable[](0);
    }
}
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4.Escrow Smart Contract: An escrow smart contract is a smart contract that can be used to facilitate secure transactions between two parties. This is an excellent way to learn how to create a smart contract that interacts with multiple parties and involves conditional transactions. The following code shows how to create a basic escrow smart contract:

pragma solidity ^0.8.0;


    contract Escrow {
        address public payer;
        address payable public payee;
        address public lawyer;
        uint256 public amount;

constructor(address _payer, address payable _payee, uint256 _amount) {
    payer = _payer;
    payee = _payee;
    lawyer = msg.sender;
    amount = _amount;
}

function deposit() payable public {
    require(msg.sender == payer, "Only payer can deposit funds.");
    require(msg.value == amount, "Deposit amount must match contract amount.");
}

function release() public {
    require(msg.sender == lawyer, "Only lawyer can release funds.");
    require(address(this).balance == amount, "Contract balance must match contract amount.");
    payee.transfer(amount);
}

function balanceOf() public view returns (uint256) {
    return address(this).balance;
}
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In this example, the escrow smart contract is used to hold funds until a condition is met. The constructor takes in the addresses of the payer and the payee, as well as the amount to be held in escrow. The deposit function can only be called by the payer and is used to deposit the funds into the contract. The release function can only be called by the lawyer and is used to release the funds to the payee once the conditions have been met. The balanceOf function can be used to check the current balance of the contract. This smart contract can be used in various scenarios such as real estate transactions or online purchases.

5.Decentralized Marketplace Smart Contract : A decentralized marketplace smart contract is a smart contract that can be used to create a decentralized marketplace where buyers and sellers can trade without intermediaries. This is an excellent way to learn how to create a smart contract that interacts with multiple parties and involves conditional transactions. The following code shows how to create a basic decentralized marketplace smart contract:

pragma solidity ^0.8.0;

contract Marketplace {
    struct Product {
        uint256 id;
        string name;
        uint256 price;
        address payable seller;
        bool sold;
    }

    mapping(uint256 => Product) public products;
    uint256 public productIndex;

    function createProduct(string memory _name, uint256 _price) public {
        require(_price > 0);
        productIndex++;
        products[productIndex] = Product(productIndex, _name, _price, payable(msg.sender), false);
    }

    function buyProduct(uint256 _id) public payable {
        require(products[_id].id != 0, "Product does not exist.");
        require(!products[_id].sold, "Product already sold.");
        require(msg.value >= products[_id].price, "Insufficient payment.");

        products[_id].seller.transfer(msg.value);
        products[_id].sold = true;
    }
}
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In this example, the decentralized marketplace smart contract is used to create a platform where buyers and sellers can trade without intermediaries. The createProduct function can be used by sellers to create a new product listing, and the buyProduct function can be used by buyers to purchase a product. The smart contract keeps track of the products, their prices, and their sellers. The buyProduct function ensures that the product exists, has not been sold already, and that the buyer has provided sufficient payment. Once the conditions are met, the smart contract transfers the payment to the seller and marks the product as sold. This smart contract can be used to create various decentralized marketplaces, such as a platform for buying and selling digital assets or a platform for peer-to-peer trading of physical goods.

Hope you will get an idea from all this different contracts and practice by creating your own contracts and deploy in mainnet or testnet using remix ide

All the best

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