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The following function computes an array $SPF$, where, for any integer $1 < i < 1000$,  $SPF[i]$ is the smallest prime factor of $i$. For example, $SPF[6]$ is $2$, and $SPF[11]$ is $11$.

There are five missing parts in the following code, commented as $/* Blank */$. For each of them, copy the entire line with the comment and fill the blank appropriately in your answer sheet.

int SPF[1000];

void findSPF() {

SPF[1] = 1;

// Initializing SPF of every number to be itself

for (int i = 2; i < 1000; i++) {
_____; /* Blank 1 */
}

// SPF of every even number is 2

for (int i = 4; i < 1000; i += 2) {

SPF[i] = _____; /* Blank 2 */
}

// For odd numbers, updating the SPFs of their multiples

for (int i = _____; i * i < 1000; i++) {

/* Blank 3 */

if (SPF[i] == i) {

// No smaller factor of i found yet

for (int j = _____; j < 1000; j+= i) {

/* Blank 4 */
if (SPF[j] == j) {

SPF[j] = _____; /* Blank 5 */
}
}
}
}
}

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