One97 Interview Question
SDE1sCountry: United States
int getPrime(int a, int b)
{
int count = 0;
for ( int i = a; i <=b ; ++i )
{
if ( isPrime(i))
{
System.out.println("Prime Number: " + i);
count ++;
}
}
return count;
}
boolean isPrime( int a)
{
boolean bIsPrime = true;
if ( a == 1 ) return false;
if ( a <= 3) return bIsPrime;
int sqrt = (int) Math.sqrt((double)a);
for (int i = 2; i <= sqrt; ++i)
{
if ( (a % i ) == 0 )
{
bIsPrime = false;
break;
}
}
return bIsPrime;
} // End isprime()
Use "Sieve of Eratosthenes" for actual count.
- lasthope November 20, 2013Approximately (A/ ln A) - (B/ ln B), using prime number theorem.