AssignmentVault.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract AssignmentVault {

    struct Submission {
        string name;
        string cid;
        uint256 time;
        address student;
    }

    Submission[] public submissions;

    function submit(string memory _name, string memory _cid) public {
        submissions.push(
            Submission(
                _name,
                _cid,
                block.timestamp,
                msg.sender
            )
        );
    }

    function get(uint256 index)
        public
        view
        returns (string memory, string memory, uint256, address)
    {
        Submission memory s = submissions[index];
        return (s.name, s.cid, s.time, s.student);
    }

    function count() public view returns (uint256) {
        return submissions.length;
    }
}