Created
March 17, 2016 06:32
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Primes in Interval (Million)
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from math import sqrt | |
#Sieve Of Eratosthenes - Start | |
last = int(sqrt(2147483647)) + 1 | |
limit = int(sqrt(last)) + 1 | |
arr = [True for i in range(0,last+1)] | |
i = 2 | |
all_primes = [] | |
while i <= limit: | |
for im in range(i*i,last+1,i): | |
arr[im] = False | |
for j in range(i+1,last+1): | |
if arr[j] == True: | |
i = j | |
break | |
for index in range(2,last+1): | |
if arr[index]: | |
all_primes.append(index) | |
#Sieve of Eratosthenes - End | |
t = int(input()) | |
for testcase in range(0,t): | |
m,n = input().split() | |
m,n = int(m),int(n) | |
answer = [] | |
#If small limit, we already have primes | |
if n <= last: | |
answer = [x for x in all_primes if x >= m and x <= n] | |
for prime in answer: | |
print(prime) | |
#If large limit, we do segmented sieve | |
else: | |
if m < 2: | |
m = 2 | |
#0 corresponds to m | |
arr = [True for x in range(m,n+1)] | |
primes = [x for x in all_primes if x <= int(sqrt(n))] | |
for prime in primes: | |
i = (m // prime) * prime | |
if i == 0: | |
i = i + (2*prime) | |
elif i == prime: | |
i = i + prime | |
elif i < m: | |
i = i + prime | |
for im in range(i,n+1,prime): | |
arr[im-m] = False | |
for j in range(m,n+1): | |
if arr[j-m] == True: | |
print(j) |
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