Some common math coding exercises used as interview programming questions

isPrime

An algorigthm to compute a Prime Number which is greater than 1 and only divisbile by one and itself. For example Prime numbers are 1,2,3,5,7,11,13,17..

Problem: Given a number n the function must determine if n is prime and return true/false.

1boolean isPrime(int n) {
2  for (int x=2; x*x <=n; x++) {
3    if (n % x == 0) {
4      return false;
5    }
6  }
7  return true;
8}

Time Complexity: Analyzing this code fragment has a time complexity of o(n/2)