### [A. Collatz Algorithm](https://mirror.codeforces.com/group/e8jUNwDnHj/contest/504495/problem/A)↵
↵
<spoiler summary="Solution">↵
```python↵
def read():↵
return int(input())↵
def read_list():↵
return [int(i) for i in input().split()]↵
↵
n = read()↵
print(n, end=' ')↵
↵
while n != 1:↵
if n % 2 == 0: ↵
n //= 2↵
else: ↵
n *= 3↵
n += 1↵
print(n, end=' ')↵
```↵
</spoiler>↵
↵
↵
### [B. DNA Counting](https://mirror.codeforces.com/group/e8jUNwDnHj/contest/504495/problem/B)↵
↵
<spoiler summary="Solution">↵
```python↵
def read():↵
return int(input())↵
def read_list():↵
return [int(i) for i in input().split()]↵
↵
↵
↵
s = input()↵
count = {}↵
a = "ACGT"↵
for c in a:↵
count[c] = 0↵
for c in s:↵
count[c] += 1↵
↵
for c in a:↵
print(count[c], end=' ')↵
```↵
</spoiler>↵
↵
### [C. TPCP 2023 – Is it a Helal Sequence?](https://mirror.codeforces.com/group/e8jUNwDnHj/contest/504495/problem/C)↵
↵
<spoiler summary="Solution">↵
```python↵
def read():↵
return int(input())↵
def read_list():↵
return [int(i) for i in input().split()]↵
↵
↵
n, x = read_list()↵
a = read_list()↵
↵
result = 1↵
for i in a:↵
result *= i↵
result %= x↵
↵
if result == 0:↵
print("yes")↵
else:↵
print("no")↵
```↵
</spoiler>↵
↵
↵
↵
↵
<spoiler summary="Solution">↵
```python↵
def read():↵
return int(input())↵
def read_list():↵
return [int(i) for i in input().split()]↵
↵
n = read()↵
print(n, end=' ')↵
↵
while n != 1:↵
if n % 2 == 0: ↵
n //= 2↵
else: ↵
n *= 3↵
n += 1↵
print(n, end=' ')↵
```↵
</spoiler>↵
↵
↵
### [B. DNA Counting](https://mirror.codeforces.com/group/e8jUNwDnHj/contest/504495/problem/B)↵
↵
<spoiler summary="Solution">↵
```python↵
def read():↵
return int(input())↵
def read_list():↵
return [int(i) for i in input().split()]↵
↵
↵
↵
s = input()↵
count = {}↵
a = "ACGT"↵
for c in a:↵
count[c] = 0↵
for c in s:↵
count[c] += 1↵
↵
for c in a:↵
print(count[c], end=' ')↵
```↵
</spoiler>↵
↵
### [C. TPCP 2023 – Is it a Helal Sequence?](https://mirror.codeforces.com/group/e8jUNwDnHj/contest/504495/problem/C)↵
↵
<spoiler summary="Solution">↵
```python↵
def read():↵
return int(input())↵
def read_list():↵
return [int(i) for i in input().split()]↵
↵
↵
n, x = read_list()↵
a = read_list()↵
↵
result = 1↵
for i in a:↵
result *= i↵
result %= x↵
↵
if result == 0:↵
print("yes")↵
else:↵
print("no")↵
```↵
</spoiler>↵
↵
↵
↵
