title: Convert string to all lower case without built-in functions
body: <pre><code>#variable defination#
  lower="abcdefghijklmnopqrstuvwxyz"
  upper="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
  valid=True
  x=0
  g=0
  
  
  string=input("enter a string:")
  
  #data validation#
  for char in string:
    if char in "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ":
       valid=True
    else:
       valid=False
  
  #finding the character#
  if valid:
    for char in string:
      g+=1
      for ele in upper:
        if char!=ele:
         x+=1
  
  
  print(lower[x]+string[g::])
  </code></pre>
  
  <p>**I can't get it to work, it keeps iterating through the entire string without the condition ever being met. **</p>