灼熱カバディの最新刊アツすぎだろ！
Bourne-Again Shell, bash
Andrew S. Tanenbaum, MINIX
I could not solve this problem during the contest. As I checked the solution, I noticed that I was very close to the answer.
2*2 square can be used to generate the same result as the operation applied on any rectangle.
So, I can focus on applying 2*2 square to a to make it
b (?), i.e., thinking about applying 2*2 square
[[1, 2], [2, 1]] or [[2, 1], [1, 2]] should be
enough to consider applying i*j square.
To convert a into b, I can iterate through
1…n-1 for rows and 1…m-1 for columns, applying
[[1, 2], [2, 1]] or [[2, 1], [1, 2]].
Feedback 215 Good problem 19 Average problem 292 Bad problem 37 Did not solve
It's interesting the community seems not to like the problem. I have little experience in competitive programming and don't know what determines whether a problem is good, and I'm grateful to the author for making the contest happen.
We can make the first n - 1 rows and m - 1 columns equal by doing
that, but we need to check if the last row and column of a
(modified) and b equal.
Note that the sum of each row and each column stays constant after each operation.
both rows and columns will get (1 + 2) mod 3 by applying the 2*2 square, so any number of operations don't change the sum mod 3 for rows and columns.
That being said, the nth row and mth column of a
(modified) and b need to have the same value after the
operations <=> Every row and colum need to have the same value
(mod 3).
def possible(n: int, m: int, a: list[int], b: list[int]) -> bool:
for rowi in range(n):
if sum(a[rowi]) % 3 != sum(b[rowi]) % 3:
return False
for coli in range(m):
asum: int = 0
bsum: int = 0
for rowi in range(n):
asum = (asum + a[rowi][coli]) % 3
bsum = (bsum + b[rowi][coli]) % 3
if asum != bsum:
return False
return True
for _ in range(int(input())):
n, m = map(int, input().split())
a: list[int] = []
b: list[int] = []
for i in range(n):
a.append(list(map(int, list(input()))))
for i in range(n):
b.append(list(map(int, list(input()))))
if possible(n, m, a, b):
print("YES")
else:
print("NO")I'm still not quite sure if I understand this problem properly.
Snacks 20g Protein shake 20g
Total carbohydrate 40g
MUST:
TODO: