ethereum/remix

pragma solidity ^0.4.21;

contract DLL {
struct Node {
uint[3][3] data;
uint prev;
uint next;
}

Node[] public nodes;
uint n = 3;
uint h=0;
function initArray() public payable {
while(h!=5)
{
    uint[3][3] memory result;
    for (uint i = 0; i < n; i++){
        for(uint j = 0; j < n; j++){
            result[i][j] = 1;
        }
    }
     nodes.push(Node(result, 0, 0));
     insert(h,result);
     h=h+1;
}
}

function insert(uint id, uint[3][3] data) public{
    require(id == 0 || isValidNode(id));
    Node storage node = nodes[id];
    uint newID;
    nodes.push(Node({
        data: data,
        prev: id,
        next: node.next
    }));
    newID = nodes.length - 1;
    nodes[node.next].prev = newID;
    node.next = newID;
}
function isValidNode(uint256 id) internal view returns (bool) {
return id != 0 && (id == nodes[0].next || nodes[id].prev != 0);

}
}