Merkle Tree Construction Issue

[jizhouli]

https://github.com/Jeiwan/blockchain_go/blob/fee9bfd3afeef02e237e93335fa2076c30b9d6d6/merkle_tree.go#L36

Please forgive my English is not very good, I want to report a issue when constructs the merkle tree. I think, the leaves number of merkle tree should be power of 2, not even, or the program will stack overflow. For example 6, when i = 1, j = 2, the index of nodes[j+1] will be out of bounds.

[123Daoxyz]

@jizhouli you may try this one.

// NewMerkleTree creates a new Merkle tree from a sequence of data
func NewMerkleTree(data [][]byte) *MerkleTree {
    var nodes []MerkleNode

    if len(data)%2 != 0 {
        data = append(data, data[len(data)-1])
    }

    for _, datum := range data {
        node := NewMerkleNode(nil, nil, datum)
        nodes = append(nodes, *node)
    }

    for i := 0; i < len(data)/2; i++ {
        var newLevel []MerkleNode

        for j := 0; j < len(nodes); j += 2 {
            node := NewMerkleNode(&nodes[j], &nodes[j+1], nil)
            newLevel = append(newLevel, *node)
        }

        nodes = newLevel

        if len(newLevel) == 1 {
            break
        }
    }

    mTree := MerkleTree{&nodes[0]}

    return &mTree
}

[Bingzo]

codes above may not fix the issue, solution here looks fine : https://github.com/Jeiwan/blockchain_go/pull/31/files