Contains

This method is part of the solution to an assignment given out in the fall of 2003. Here is the description of the method as given in the assignment:

/**
* Return whether s contains every letter in t. For example,
* "abcd" contains all the letters in "bbdc", since every letter
* in the second String appears in the first.
* Precondition: s != null && t != null.
*/
public static boolean contains(String s, String t)

Download files: Contains.java
Areas: Introduction to loops.

Contains.java

1	/**
2	* Return whether s contains every letter in t. For example,
3	* "abcd" contains all the letters in "bbdc", since every letter
4	* in the second String appears in the first.
5	* Precondition: s != null && t != null.
6	*/
7	public static boolean contains(String s, String t) {
8	boolean contains= true;
9	for(int i= 0; contains && i < t.length(); i++) {
10	contains= contains && (s.indexOf(t.charAt(i)) >= 0);

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Question 1

When this method returns, the variable contains has the obvious meaning: it is true if and only if s contains every letter of t. What is the meaning of contains when tested at the top of the for-loop on line 9, while i=n and t.length()>n?