Ok,I have learnt how to generate prime numbers and how to 'split'
input.The above was to help me solve the second 'SPOJ'
challenge,PRIME1.The challenge can be found at
<https://www.spoj.pl/problems/classical/sort=0,start=0>
I have written my solution and tested it and it works fine,but
unfortunately it is times out when tested by 'SPOJ'.I don't know whether
it times out because it is inherently slow or because a certain
condition takes it into endless loops.I think it is simply because it
needs further optimisation.I have researched as much as I could but
can't find any way to improve the speed of the program (problem with
being a newbie is you don't know what you don't know!)
Could you please look at the program (attached) and advise possible
optimisations or point me to possible resources that would help solve
this challenge.
Thanks,
Boyks
#!/usr/bin/env python
'''A program to generate prime numbers when given 2 numbers'''
def isPrime(number):
number=abs(int(number))
#1 is not considered a prime number
if number<2:
return False
#2 is the only even prime number
if number==2:
return True
#no even prime numbers after 2
if not number&1:
return False
#to find all prime numbers we need to go up to the
#square root of the highest odd number
for x in range(3,int(number**0.5)+1,2):
if number%x==0:
return False
return True
def printOutListOfPrimes(startNum,endNum):
#startNum and endNum commented out.Will be collected from user input
#startNum=int(raw_input())
#endNum=int(raw_input())
for num in range(startNum,endNum):
check=isPrime(num)
if check==1:
print num
def getNumOfTimes():
times=int(raw_input())
return times
print times
def getValues():
val=[]
n=getNumOfTimes()
for r in range(n):
input=raw_input()
newInput=input.split()
# val.append(newInput)
val+=newInput
return val
if __name__ == "__main__":
x=getValues()
y=0#variable to control the indices
for i in range(len(x)-1):
y=0 #to keep track of indices
printOutListOfPrimes(int(x[y]),int(x[y+1]))
print
y+=2
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