EPISODES - Editorial

editorial
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PROBLEM LINK:

Practice
Contest: Division 1
Contest: Division 2
Contest: Division 3
Contest: Division 4

Author: raysh07
Tester: sushil2006
Editorialist: iceknight1093

DIFFICULTY:

Cakewalk

PREREQUISITES:

None

PROBLEM:

A series has N episodes, each being K minutes long.
How much time, in hours and minutes, does it take to watch them all?

EXPLANATION:

N episodes and K minutes makes for a total of N\times K minutes worth of time.

We then need to convert N\times K to the (hour, minute) format.
There are a couple of ways of doing this:

  1. The brute-force approach.
    Start with H = 0 and M = N\times K.
    Then, as long as M \ge 60, subtract 60 from M and add 1 to H, essentially repeatedly converting 60 minutes into one hour.
    In the end, the answer is the final values of H and M.
  2. The math approach.
    This is the same as the previous one, but with the additional observation that the repeated subtraction can be emulated by division.
    That is, H will just equal the quotient when (N\times K) is divided by 60, while M will equal the remainder of the division.
    So, you can directly print said quotient and remainder.

TIME COMPLEXITY:

\mathcal{O}(1) per testcase.

CODE:

Editorialist's code (PyPy3) 
for _ in range(int(input())):
    n, k = map(int, input().split())
    mins = n*k
    print(mins//60, mins%60)