PROBLEM LINK:
Practice
Contest: Division 1
Contest: Division 2
Contest: Division 3
Contest: Division 4
Author: Utkarsh Gupta
Tester: Hriday
Editorialist: Nishank Suresh
DIFFICULTY:
641
PREREQUISITES:
None
PROBLEM:
There are N cards, out of which X are face-down. How many cards do you need to flip so that every card faces the same direction?
EXPLANATION:
To make every card face-down, we need to flip each of the N-X cards that are currently face-up.
To make every card face-up, we need to flip each of the X cards that are currently face-down.
Making every card face the same way thus needs the minimum of these two values, i.e, \min(X, N-X) flips.
TIME COMPLEXITY
\mathcal{O}(1) per test case.
CODE:
Editorialist's code (Python)
for _ in range(int(input())):
n, k = map(int, input().split())
print(min(k, n-k))