Brute Force

The brute force approach tries every possible combination to check for a solution, without leveraging any special properties or optimizations of the data (such as sorted order). Typically involves: 

• Nested loops
  • Outer Loop traverses the array for the first element of the pair
  • Inner Loop traverses the rest of the array to find second element 
• Recursion 

Drawbacks:

• • Time Complexity: Typically O(n²) or slower, impractical for large datasets.
  • Redundancy: Many computations are repeated unnecessarily

Need to know: Nested For Loops, Range, Len

def brute_force_two_sum(nums, target):
    # Iterate through each element in the list
    for i in range(len(nums)):
        # For each element, check every other element that comes after it
        for j in range(i + 1, len(nums)):
            # Check if the current pair sums to the target
            if nums[i] + nums[j] == target:
                return (i, j)  # Return the indices as a tuple
    # If no pair is found that adds up to the target, return None
    return None

# Example usage:
nums = [2, 7, 11, 15]
target = 9

result = brute_force_two_sum(nums, target)
if result:
    print("Pair found at indices:", result)
else:
    print("No pair found that adds up to the target.")

 

Great question — no, nested for loops in Python don't always have to use range(). It totally depends on what you're looping over.

Let’s break this down:

---

✅ When You Use range() in Nested Loops

You use range() when you're looping over indexes, usually for:

• Arrays

• Matrices

• Iterations with index math

for i in range(len(matrix)):
    for j in range(len(matrix[0])):
        print(matrix[i][j])

---

✅ When You Don’t Need range()

You can also loop directly over values — nested or not — when index access isn't needed.

Example: Nested Lists

for row in matrix:
    for val in row:
        print(val)

Example: Nested Dictionaries

for category, items in asset_dict.items():
    for item in items:
        print(f"{category}: {item}")

Example: In Tech Art (Blender)

for obj in bpy.data.objects:
    for modifier in obj.modifiers:
        print(f"{obj.name} has modifier {modifier.name}")

---

🧠 When to Use range() vs Direct Loop

Use Case	Use range()	Direct Loop (for item in list)
You need the index ✅	✅ Yes	❌ No
You only care about the value	❌ No	✅ Yes
You're modifying a list in-place	✅ Often	❌ Risky

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So nested loops can use range(), but they only should when you need an index or are doing some kind of math-based traversal (e.g., comparing elements, jumping steps, etc).

Want me to show a nested loop example with range() from a LeetCode matrix problem or a nested asset traversal from a DCC pipeline?