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Practice
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Contest: Division 4

Author: pols_agyi_pols
Tester: kingmessi
Editorialist: iceknight1093

DIFFICULTY:

Cakewalk

PREREQUISITES:

None

PROBLEM:

Chef is at point X. He has 2Y friends - one at each position in [X-Y, X+Y] except for X itself.
He can only visit friends within a range of Z, i.e. within [X-Z, X+Z].
How many friends can be visited?

EXPLANATION:

If Z \ge Y, then Chef will be able to visit all his friends.
In this case, the answer is the number of Chef’s friends - which is 2Y.

If Z \lt Y, then some of Chef’s friends are too far away to visit.
Chef can only visit the friends in range [X-Z, X+Z].
There’s one friend at each position in this range (other than X), so the count of friends who can be visited is 2Z.

Both cases can be combined into a single formula: the answer is simply

2\cdot \min(Y, Z)

TIME COMPLEXITY:

\mathcal{O}(1) per testcase.

CODE:

Editorialist's code (PyPy3)
for _ in range(int(input())):
    x, y, z = map(int, input().split())
    print(2*min(y, z))