title: What is the working and output of getLayerNames() and getUnconnecteddOutLayers() functions?
body: <p>I almost searched every where on internet but i could not find out the working and output of below functions. Specially what they do in <code>YOLO</code> algorithm.</p>
  
  <pre><code>getLayerNames()
  getUnconnectedOutLayers()
  </code></pre>
  
  <p>code is as follows:</p>
  
  <pre><code>import cv2 
  import numpy as np 
  import time 
  #Loading Yolo 
  net = cv2.dnn.readNet("yolov3.weights", "yolov3.cfg") 
  classes = [] 
  with open("coco.names", "r") as f: 
    classes = [line.strip() for line in f.readlines()] 
  layer_names = net.getLayerNames() 
  outputlayers=[layer_names[i[0] - 1] for i in net.getUnconnectedOutLayers()] 
  </code></pre>