CSci 1211 Problem set 5

CSci 1211 Problem set 5. Due Friday, Feb. 20th at 5pm

Problem 1 (8 points)

Write a program to read an integer from the user's input and print out the following two triangles (assuming the user entered 5):


*****
 ****
  ***
   **
    *
    *
   **
  ***
 ****
*****

You may use the solution to the first two lab questions (the upper left and the lower left triangles).

Problem 2 (5 points)

Write a program that will read a string and print it out so that letters at even-numbered positions (0, 2, etc.) are capitalized and letters at odd-numbered positions are lower case. Non-letter characters are not changed.

Hint: to convert a Java character into upper case, you need to use the method Character.toUpperCase(). Here is an example:


char c = 'a';
c = Character.toUpperCase(c); // create 'A', store it in c

(use Character.toLowerCase(c) to convert to lower-case). Alternatively you can create two additional strings: an upper-case version of the input string and the lower-case one and copy or print characters from those strings.

Here is a sample run of a program using some weird Russian name as an input :-)


Please enter a string: elena MACHKASOVA

The result is: ElEnA MaChKaSoVa

4 points of extra credit will be given if your program doesn't use an if/else statement inside the loop. The program must work correctly on all strings.

Problem 3 (5 points)

Write a program that reads integer numbers as input from the user and counts the number of odd and even numbers. The program stops when the user enters -1. At the end the program displays the two counts. It also prints out a message saying whether there has been more odd or even numbers.

Problem 4 (8 points)

Problem 18 p. 159. Clarification: compute the "intrinsic" sine function using Math.sin (see p. 43).

Problem 5 (7 points)

Write a program that reads strings from the user while the strings are in alphabetical order (from a to z). The first string that comes out of order stops the program. Here is an example of how the program works:


Please enter a string: apple
Please enter a string: banana
Please enter a string: grape
Please enter a string: orange
Please enter a string: kiwi
kiwi comes before orange. Good bye!

You may assume that all the strings are lower-case.

This page is a part of the course CSci 1211 at UMM.