Next prime

help
1

Given a number n. Find its next prime

Constraint : n<=10^9
Time : 1 sec

Is there any good approach

If yes pls share

2 
#Here is the python implementation
n=int(input())
if n%2==0:
       st=n+1
else:
       st=n+2
for I in range(st, 10**9 +8, 2):
       if is_prime(i):
             res=I
             break
#res is your answer
print (res)
3

Sieve algorithm should work…but constraint are high… So.

4

The naive iterative approach should work because we have to check at most 10^6 or less to find next prime.