Euler Project #3 Largest prime factor Timeout
I have been recently trying my hands on Euler's Project through HackerRank and got stuck with project #3 where you have to find the Largest Prime Factor.
Question: The prime factors of 13195 are 5, 7, 13 and 29.
What is the largest prime factor of a given number N?
I have written two different codes which both works for the first four problems in HackerRank but timeout on the last two. Please let me know how I can optimize my code further so that the timeout doesn't occur.
Code #1
for a in range(int(input())):
n = int(input())
b = n//2
i=1
if b%2==1:
i+=1
max=1
while b > 2:
if n%b==0:
isprime = True
for c in range(2,int(b**0.5)+1):
if b%c==0:
isprime = False
break;
if isprime:
max = b
break;
b-=i
if max==1:
max=n
print(max)
This one tries to find the first largest numbers which can divide a particular number and then tries to find whether it is a prime.
Code #2
for a in range(int(input())):
n = int(input())
num = n
b = 2
max=1
while n > 1 and b < (num//2)+1:
if n%b==0:
n//=b
max=b
b+=1
if max==1:
max=n
print(max)
This basically tries to find the last largest factor by multiple division.
python beginner python-3.x programming-challenge
asked 13 mins ago
remedcuremedcu
1004
add a comment |
I have been recently trying my hands on Euler's Project through HackerRank and got stuck with project #3 where you have to find the Largest Prime Factor.
Question: The prime factors of 13195 are 5, 7, 13 and 29.
What is the largest prime factor of a given number N?
I have written two different codes which both works for the first four problems in HackerRank but timeout on the last two. Please let me know how I can optimize my code further so that the timeout doesn't occur.
Code #1
for a in range(int(input())):
n = int(input())
b = n//2
i=1
if b%2==1:
i+=1
max=1
while b > 2:
if n%b==0:
isprime = True
for c in range(2,int(b**0.5)+1):
if b%c==0:
isprime = False
break;
if isprime:
max = b
break;
b-=i
if max==1:
max=n
print(max)
This one tries to find the first largest numbers which can divide a particular number and then tries to find whether it is a prime.
Code #2
for a in range(int(input())):
n = int(input())
num = n
b = 2
max=1
while n > 1 and b < (num//2)+1:
if n%b==0:
n//=b
max=b
b+=1
if max==1:
max=n
print(max)
This basically tries to find the last largest factor by multiple division.
python beginner python-3.x programming-challenge
asked 13 mins ago
remedcuremedcu
1004
add a comment |
I have been recently trying my hands on Euler's Project through HackerRank and got stuck with project #3 where you have to find the Largest Prime Factor.
Question: The prime factors of 13195 are 5, 7, 13 and 29.
What is the largest prime factor of a given number N?
I have written two different codes which both works for the first four problems in HackerRank but timeout on the last two. Please let me know how I can optimize my code further so that the timeout doesn't occur.
Code #1
for a in range(int(input())):
n = int(input())
b = n//2
i=1
if b%2==1:
i+=1
max=1
while b > 2:
if n%b==0:
isprime = True
for c in range(2,int(b**0.5)+1):
if b%c==0:
isprime = False
break;
if isprime:
max = b
break;
b-=i
if max==1:
max=n
print(max)
This one tries to find the first largest numbers which can divide a particular number and then tries to find whether it is a prime.
Code #2
for a in range(int(input())):
n = int(input())
num = n
b = 2
max=1
while n > 1 and b < (num//2)+1:
if n%b==0:
n//=b
max=b
b+=1
if max==1:
max=n
print(max)
This basically tries to find the last largest factor by multiple division.
python beginner python-3.x programming-challenge
asked 13 mins ago
remedcuremedcu
1004
I have been recently trying my hands on Euler's Project through HackerRank and got stuck with project #3 where you have to find the Largest Prime Factor.
Question: The prime factors of 13195 are 5, 7, 13 and 29.
What is the largest prime factor of a given number N?
I have written two different codes which both works for the first four problems in HackerRank but timeout on the last two. Please let me know how I can optimize my code further so that the timeout doesn't occur.
Code #1
for a in range(int(input())):
n = int(input())
b = n//2
i=1
if b%2==1:
i+=1
max=1
while b > 2:
if n%b==0:
isprime = True
for c in range(2,int(b**0.5)+1):
if b%c==0:
isprime = False
break;
if isprime:
max = b
break;
b-=i
if max==1:
max=n
print(max)
This one tries to find the first largest numbers which can divide a particular number and then tries to find whether it is a prime.
Code #2
for a in range(int(input())):
n = int(input())
num = n
b = 2
max=1
while n > 1 and b < (num//2)+1:
if n%b==0:
n//=b
max=b
b+=1
if max==1:
max=n
print(max)
This basically tries to find the last largest factor by multiple division.
python beginner python-3.x programming-challenge
python beginner python-3.x programming-challenge
asked 13 mins ago
remedcuremedcu
1004
asked 13 mins ago
remedcuremedcu
1004
asked 13 mins ago
remedcuremedcu
1004
asked 13 mins ago
remedcuremedcu
1004
asked 13 mins ago
remedcuremedcu
1004
1004
add a comment |
add a comment |
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