# CS 240: Lecture 8 - Pause

Dear students:

With a programming assignment due soon, we decided it would be best to dedicate a day for review and questions. Today we will work through some analysis problems together and discuss the problems you are encounter on the programming assignment or lab.

## Analysis As we have time, we will work through the analysis of these algorithms:

• public static boolean isSpecial(int n) {
for (int i = 2; i * i <= n; ++i) {
if (n % i == 0) {
return false;
}
}
return true;
}
• public static int perhaps(int[] xs, int z) {
int i = 0;
int j = xs.length - 1;

while (i <= j) {
int k = (i + j) / 2;
if (xs[k] == z) {
return k;
} else if (xs[k] < z) {
i = k + 1;
} else {
j = k - 1;
}
}

return -1;
}
• public static double calculate(double[] xs) {
double y = 0.0;
for (double x : xs) {
y += x;
}
y = y / xs.length;

double z = 0.0;
for (double x : xs) {
w = x - y;
z += w * w;
}

return z / (xs.length - 1);
}
• public static boolean maybe(String[] items) {
for (int i = 0; i < items.length; ++i) {
if (items.length > 10) {
return false;
}
}
return true;
}

## TODO You've got a few things to do before we meet again:

See you next time!

Sincerely, 