Read the question, write Python on the right, then Run or Check.
QuestionHint and solution stay closed until you open them
Write is_prime(n) that returns True if n is a prime number, else False.
main already reads n and prints yes or no. 1 is not prime. 2 is.
Input. One line: an integer n ≥ 1.
Output. yes or no.
Constraints
- 1 ≤ n ≤ 10,000
Examples
Input
7
Output
yes
Input
1
Output
no
Input
9
Output
no
Hint
- Return False immediately for n < 2.
- Trial-divide from 2 through int(n**0.5). If any divisor hits, it is composite.
Show correct code
Peek only after you have tried. You can still Check your own version.
def is_prime(n):
if n < 2:
return False
d = 2
while d * d <= n:
if n % d == 0:
return False
d += 1
return True
n = int(input())
print("yes" if is_prime(n) else "no")
main.pyPython · Ctrl + Enter runs
ResultIdle
Run to see output. Check grades the tests.