def getNumBlocksToMine(chanBlocks):
    """
    get number blocks to mine to fund the channels including extra 100 to spend the blocks
    :param chanBlocks: the outputs of coinbase txs put in blocks
    :return: int
    """
    cbs = 0
    for block in chanBlocks:
        cbs += len(block)
    blocksToMine = cbs + 100
    return blocksToMine