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Update _204.java (fishercoder1534#70)

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Original file line number	Diff line number	Diff line change
`@@ -48,7 +48,9 @@ private boolean isPrime(int num) {`
`48`	`48`	`But don't let that name scare you, I promise that the concept is surprisingly simple.`
`49`	`49`
`50`	`50`	`Sieve of Eratosthenes: algorithm steps for primes below 121. "Sieve of Eratosthenes Animation" by SKopp is licensed under CC BY 2.0.`
`51`		`- We start off with a table of n numbers. Let's look at the first number, 2. We know all multiples of 2 must not be primes, so we mark them off as non-primes. Then we look at the next number, 3. Similarly, all multiples of 3 such as 3 × 2 = 6, 3 × 3 = 9, ... must not be primes, so we mark them off as well. Now we look at the next number, 4, which was already marked off.`
	`51`	`+ We start off with a table of n numbers. Let's look at the first number, 2. We know all multiples of 2 must not be primes, so we mark`
	`52`	`+ them off as non-primes. Then we look at the next number, 3. Similarly, all multiples of 3 such as 3 × 2 = 6, 3 × 3 = 9, ... must not`
	`53`	`+ be primes, so we mark them off as well. Now we look at the next number, 4, which was already marked off.`
`52`	`54`	`What does this tell you? Should you mark off all multiples of 4 as well?`
`53`	`55`	`4 is not a prime because it is divisible by 2, which means all multiples of 4 must also be divisible by 2 and were already marked off.`
`54`	`56`	`So we can skip 4 immediately and go to the next number, 5.`

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