#Write an efficient program for writing first prime number greater than a given number
import sys
import time
f=open('c:\inputs\in3_5.txt','r')
n=int(f.readline())
f.close()
t1=time.clock()
no_div=0
while (1):
    n=n+1
    if n < 2:
        fg=0
    elif n==2:
        fg=1
    elif not n & 1:# all other even numbers are not primes
        fg=0
   
    else:
        x=3
        
        while(x<=n**0.5):
            no_div=no_div+1
            if n % x == 0:
                fg=0
                break
            else:
                fg=1
                x=x+2    
    if(fg==1):
        break

t2=time.clock()
t= t2-t1
mem=sys.getsizeof(n)+sys.getsizeof(no_div)+sys.getsizeof(fg)+sys.getsizeof(x)
f1=open('out_15_sec3_5.txt','w')
f1.write("Next prime=%d \nno. of divisions=%d \ntime taken="%(n,no_div))
f1.write(str(t))
f1.write("seconds\nmemory used=%d bytes"%mem)
f1.close()