CodingBat Interlude

We are studying something easy for the two days at the end of the quarter.

• Make an account on CodingBat.com. Do not use a valuable password.

• Wednesday, November 1:

  • Read about logical operations in Java.
  • See below for a quick summary.
  • Do eight problems from Logic-1 or higher.

• Thursday, November 2:

  • Read about for and while loops .
  • Read about arrays which provide a context for using for.
  • See below for a quick summary.
  • Do eight problems from Arrays-2.

Summary of Logical Operations

• if - else if - else
• and(&&), or (||), not (!)

public boolean someFunction (int n)
{
  boolean answer = false;
  
  if ( n > 20 ) {
    answer = true;
  } else {
    answer = ( n < -10);
  }
  
  return answer;
}

Summary of Looping

• arrayname.length finds the length of the array
• arrayname[index] gets the the value at the given index
• for (set starting value; test to continue; what to do between steps) { … }

public int countNines (int[] nums)
{
  int count = 0;
  for (int k = 0; k < nums.length; k++)
  {
    if (nums[k] == 9) 
    {
      count = count + 1;
    }
  }
  return count;
}