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Merge Sort Algorithm

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Merge Sort Algorithm

Merge Sort Algorithm is a DSA idea you prove with names A→Z, not with a slogan.

Keep Merge Sort Algorithm small. Dev should finish names A→Z in a few lines, not a 40-line dump.

Skip Merge Sort Algorithm and unstable sort when equal keys matter shows up in the roll list.

Dev ships Merge Sort Algorithm in the roll list. That is the use case worth saying.

Merge Sort Algorithm miss — unstable sort when equal keys matter. Fix it before you talk about advanced DSA.

Place Merge Sort Algorithm next to nearby DSA work — n log n vs n² is the link.

Close Merge Sort Algorithm with — “If I skip it, names A→Z goes wrong like this: unstable sort when equal keys matter.”

Exam tip

Say Merge Sort Algorithm in one breath, then n log n vs n², then unstable sort when equal keys matter.

Example

def merge_sort(arr):
    if len(arr) <= 1:
        return arr
    mid = len(arr) // 2
    left = merge_sort(arr[:mid])
    right = merge_sort(arr[mid:])
    out, i, j = [], 0, 0
    while i < len(left) and j < len(right):
        if left[i] <= right[j]:
            out.append(left[i]); i += 1
        else:
            out.append(right[j]); j += 1
    return out + left[i:] + right[j:]

print(merge_sort([5, 1, 4, 2]))

Merge Sort Algorithm — merge sort divides the array, sorts halves, then merges — O(n log n).

Short notes

DefMerge Sort Algorithm — Dev uses it for names A→Z in the roll list.
RuleMerge Sort Algorithm → n log n vs n².
RememberMerge Sort Algorithm + time vs memory (the roll list).
UseMerge Sort Algorithm in the roll list (names A→Z).
TrapMerge Sort Algorithm — unstable sort when equal keys matter.
ExMerge Sort Algorithm → names A→Z.

def merge_sort(arr): if len(arr) <= 1: return arr mid = len(arr) // 2 left = merge_sort(arr[:mid]) right = merge_sort(arr[mid:]) out, i, j = [], 0, 0 while i < len(left) and j < len(right): if left[i] <= right[j]: out.append(left[i]); i += 1 else: out.append(right[j]); j += 1 return out + left[i:] + right[j:] print(merge_sort([5, 1, 4, 2]))

Merge Sort Algorithm

Example

Short notes

Questions

Merge Sort Algorithm

Example

Short notes

Questions