String Methods and Characters

The following method will return true if and only if:

• s starts with two or more of the same characters

• s contains two or more of the same characters

• s contains two or more of the same character in a row

• s ends with two or more of the same characters

• s.charAt(0) == s.charAt(1)

Susan is 5 years older than Matt. Three years from now Susan’s age will be twice Matt’s age. What should be in place of the following condition to solve this problem?

• s == (m - 5) && (2 * s + 3) == (m + 3)

• (s == m - 5) && (s - 3 == 2 * (m - 3))

• (s == (m + 5)) && ((s + 3) == (2 * m + 3))

• s == m + 5 && s + 3 == 2 * m + 6

Assuming that x and y have been declared as valid integer values, which of the following is equivalent to this statement?

• (x > 15 && x < 18) && (x > 10)

• (y < 20) || (x > 15 && x < 18)

• ((x > 10) || (x > 15 && x < 18)) || (y < 20)

• (x < 10 && y > 20) && (x < 15 || x > 18)

Given the following method declaration, what will redo(82, 3) return?

• 5

• 4

• 6

• 7

"foxtrot".substring(3, 5)

What is returned by the substring above?

• tr

• xtr

• xr

• fotot

"tictactoe".indexOf( 'e' )

What is returned by indexOf?

• 7

• 8

• 9

• 10

What does the following segment of Java code print out?

• 4.5 5

• 4.5 4

• 4.5 4.0

• 4.5 4.5

What is printed?

• 1223344556

• 123456

• 112233445566

• 123234345456

Assume that x and y are boolean variables and have been properly initialized.

(x && y) || !(x && y)

• true only when x is true and y is true.

• always true.

• true only when x and y have different values.

• true only when x and y have the same value.

Consider the following code segment:

if ( x > 0) x = -x;

if (x < 0) x = 0;

Which of the following is this equivalent to?

• if (x > 0) x = -x;

  else x = 0;

• if ( x < 0) x = 0;

  else x = -1;

• if (x > 0) x = 0;

• x = 0;

• if (x < 0) x = 0;