Difference between revisions of "CISC181 F2017 Lab1"

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(static int countOccurrences(char c, String S))
(static int countOccurrences(char searchChar, String S))
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* Let the program end (no loop -- just print prompt, read response, and execute ''one'' time)
 
* Let the program end (no loop -- just print prompt, read response, and execute ''one'' time)
  
===<tt>static int countOccurrences(char searchChar, String S)</tt>===
+
===<tt>static int countOccurrences(char searchChar, String searchString)</tt>===
  
Iterate through every character in the String S and count how many times char searchChar occurs.  Return this value.
+
Iterate through every character in the String searchString and count how many times char searchChar occurs.  Return this value.
  
 
===<tt>static void drawLayeredPyramid(int numLayers, char firstChar, char secondChar)</tt>===
 
===<tt>static void drawLayeredPyramid(int numLayers, char firstChar, char secondChar)</tt>===

Revision as of 21:47, 11 September 2017

  • Make a new project (but now n = 1) following these instructions
  • Name your class "Lab1". This happens when you are creating a new module, in the Java class name field
    • Add your name and section number in a comment before the class declaration
    • As explained in the subsections below, modify static void main() and create two other methods: static void countOccurrences() { ... } and static void printLayeredPyramid() { ... }
  • Submit your Lab1.java on Sakai by Monday, September 18

static void main(String[] args)

Your main() should do the following:

  • Ask the user (using println() or printf()) to input a single character and a string, each on separate lines. Read these with a Scanner object and pass them to countOccurrences().
  • Whatever value is returned by countOccurrences(),
  • If a valid choice is made, call the corresponding function immediately. Otherwise print an error message
  • Let the program end (no loop -- just print prompt, read response, and execute one time)

static int countOccurrences(char searchChar, String searchString)

Iterate through every character in the String searchString and count how many times char searchChar occurs. Return this value.

static void drawLayeredPyramid(int numLayers, char firstChar, char secondChar)

Consider the following pattern:

$$$$$$$$$$
 ¢¢¢¢¢¢¢¢¢
  $$$$$$$$
   ¢¢¢¢¢¢¢
    $$$$$$
     ¢¢¢¢¢
      $$$$
       ¢¢¢
        $$
         ¢

It consists of 10 alternating rows of $ and ¢ characters. The first row has 10 columns of characters, and each successive row has one less. drawLayeredPyramid() should make a similar pattern with numRows rows, alternating characters firstChar and secondChar.