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53 lines
1004 B
Python
53 lines
1004 B
Python
"""
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File: complexity_exercises.py
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Created Time: 2026-08-18
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Author: Hello Algo Team
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"""
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def sum_iter(n: int) -> int:
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"""Sum using iteration"""
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res = 0
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for i in range(1, n + 1):
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res += i
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return res
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def sum_recur(n: int) -> int:
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"""Sum using recursion"""
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if n == 1:
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return 1
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return n + sum_recur(n - 1)
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def linear_loop(n: int) -> int:
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"""Linear-time loop"""
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res = 0
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for i in range(n):
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res += i
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return res
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def quadratic_loop(n: int) -> int:
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"""Quadratic-time loop"""
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res = 0
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for i in range(n):
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for j in range(i, n):
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res += j
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return res
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def logarithmic_loop(n: int) -> int:
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"""Logarithmic-time loop"""
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while n > 1:
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n //= 2
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return n
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if __name__ == "__main__":
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assert sum_iter(1) == sum_recur(1) == 1
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assert sum_iter(4) == sum_recur(4) == 10
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assert linear_loop(4) == 6
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assert quadratic_loop(4) == 20
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assert logarithmic_loop(4) == logarithmic_loop(5) == 1
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