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Python: Built-in Functions vs. For & If Loops – 5 Programs Explained

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Python’s built-in functions make coding fast and efficient. But understanding how they work under the hood is crucial to mastering Python. This post shows five Python tasks, each implemented in two ways: Using built-in functions Using for loops and if statements ✅ 1. Sum of a List ✅ Using Built-in Function: numbers = [ 10 , 20 , 30 , 40 ] total = sum (numbers) print ( "Sum:" , total) 🔁 Using For Loop: numbers = [ 10 , 20 , 30 , 40 ] total = 0 for num in numbers: total += num print ( "Sum:" , total) ✅ 2. Find Maximum Value ✅ Using Built-in Function: values = [ 3 , 18 , 7 , 24 , 11 ] maximum = max (values) print ( "Max:" , maximum) 🔁 Using For and If: values = [ 3 , 18 , 7 , 24 , 11 ] maximum = values[ 0 ] for val in values: if val > maximum: maximum = val print ( "Max:" , maximum) ✅ 3. Count Vowels in a String ✅ Using Built-ins: text = "hello world" vowel_count = sum ( 1 for ch in text if ch i...
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Hadoop: How to find which file is healthy

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Hadoop provides file system health check utility which is called "fsck". Basically, it checks the health of all the files under a path It also checks the health of all the files under the '/'(root).
  • BIN/HADOOP fsck / - It checks the health of all the files
  • BIN/HADOOP fsck /test/ - It checks the health of files under the path
By default fsck utility cannot do anything for under replicated blocks and over replicated blocks. Hadoop itself heal the blocks.
Healthy file checking ides

 How to find which file is healthy

  • It prints out dot for each healthy file
  • It will print a message for each file, if it is not healthy, also for under replicated blocks, over replicated blocks, mis-replicated blocks, and corrupted blocks.
  • By default fsck utility cannot do anything for under replicated blocks and over replicated blocks. Hadoop itself heal the blocks.

How to delete corrupted blocks

  • BIN/HADOOP fsck -delete block-names
  • It will delete all corrupted blocks
  • BIN/HADOOP fsck -move block-names
  • It will move corrupted blocks to /lost directory
  • Other options we can use with fsck:
    • files
    • blocks
    • locations

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