1. **Map function** —Fast I/O** — Python's default input() is too slow for massive test cases. You can override it with sys.stdin.readline to prevent Time Limit Exceeded (TLE) errors.↵
*import sys*↵
*input = sys.stdin.readline*↵
2. **Map function** — While taking an integer array input in python we can easily take it through the map function and using the code mentioned below we can directly change it into a list.↵
_*var = list(map(int,input().split()))_*↵
2*n, k = map(int, input().split())*↵
3. **Max-Min-Sum function**—— To get the maximum or, minimum, or total sum value from a list.↵
_ without writing manual loops.↵
*val = max(var)_*↵
3*total = sum(var)*↵
4. **Sort**—— For sorting an array [Remember the sort() method doesn't return the sorted list. Rather it sorts the list in place and returns None. Therefore, assigning var.sort() in a variable will make ait equal to None].↵
_*var.sort()_*↵
_*print(var)_*↵
45. **List Comprehension** :— You can directly perform loops inside a Llist.↵
_ to initialize arrays in one clean line.↵
*lis = [i for i in range(10)]_*↵
5*zeros = [0] * 10*↵
6. **Array Output**:— For array output you can use two methods. 1. _*print((" ").join(map(str,array)))_ or simply _print(*array)_↵
↵
↵
* or simply *print(*array)*↵
7. **Recursion Limit** — Python has a low default recursion depth limit. You must increase it to avoid a RecursionError when writing Depth First Search (DFS).↵
*import sys*↵
*sys.setrecursionlimit(10**6)*↵
8. **Collections Module** — Never use list.pop(0) as it takes $O(N)$ time. Use deque for fast appends and pops from both ends, or Counter for instant frequency counting.↵
*from collections import deque, Counter*↵
*q = deque([1, 2, 3])*↵
*freq = Counter(var)*↵
9. **Math Module** — Don't write your own functions for basic math. Python has highly optimized built-in functions for GCD, LCM, ceilings, and floors.↵
*import math*↵
*g = math.gcd(12, 18)*↵
10. **Strings and Characters** — Strings are immutable, so you cannot change characters directly. Use ord() and chr() to convert between characters and their ASCII integer values.↵
*pos = ord('d') — ord('a')*↵
*rev_s = s[::-1]*↵
11. **Bisect Module** — Python's built-in module for performing Binary Search on sorted arrays instantly without writing manual loops.↵
*import bisect*↵
*idx = bisect.bisect_left(var, 3)*↵
↵
*import sys*↵
*input = sys.stdin.readline*↵
2. **Map function** — While taking an integer array input in python we can easily take it through the map function and using the code mentioned below we can directly change it into a list.↵
3. **Max-Min-Sum function**
_
*val = max(var)
4. **Sort**
_
*lis = [i for i in range(10)]
6. **Array Output**
↵
↵
7. **Recursion Limit** — Python has a low default recursion depth limit. You must increase it to avoid a RecursionError when writing Depth First Search (DFS).↵
*import sys*↵
*sys.setrecursionlimit(10**6)*↵
8. **Collections Module** — Never use list.pop(0) as it takes $O(N)$ time. Use deque for fast appends and pops from both ends, or Counter for instant frequency counting.↵
*from collections import deque, Counter*↵
*q = deque([1, 2, 3])*↵
*freq = Counter(var)*↵
9. **Math Module** — Don't write your own functions for basic math. Python has highly optimized built-in functions for GCD, LCM, ceilings, and floors.↵
*import math*↵
*g = math.gcd(12, 18)*↵
10. **Strings and Characters** — Strings are immutable, so you cannot change characters directly. Use ord() and chr() to convert between characters and their ASCII integer values.↵
*pos = ord('d') — ord('a')*↵
*rev_s = s[::-1]*↵
11. **Bisect Module** — Python's built-in module for performing Binary Search on sorted arrays instantly without writing manual loops.↵
*import bisect*↵
*idx = bisect.bisect_left(var, 3)*↵
↵
