String Methods

AP Computer Science A· difficulty 4/5

Consider:

<code class="language-java">public static int countAA(String s) { int i = 0, n = 0; while ((i = s.indexOf("AA", i)) != -1) { n++; i++; } return n; } </code></pre> What does <code>countAA("AAAAA")</code> return?

  • A

    3

  • B

    5

  • C

    2

  • D

    4

    check_circle

Explanation

Because i is incremented by 1 (not 2), occurrences may overlap. Matches start at indices 0,1,2,3 -> 4 occurrences in "AAAAA".

Want 10 more like this — adaptive to your weak spots?

Related questions