Programming Basics
using
Real-life examples
Activities
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Recipe
Assembly instructions for a toy
Map out the plan at amusement park
A busy day schedule
What is the common idea for all these activities?
Programming problem:
Using sequence structure
• Compute the weighted score based on
individual assignments’ scores. Let us say
there are only 3 assignments & 2 exams, each
with max score of 100. Respective weights are
(10%, 10%, 10%, 35% and 35%)
• Sample input & output:
Input: 100 100 100 95 95
Output: 96.5%
Pseudocode
Prompt & get the score for assignment1
Prompt & get the score for assignment2
Prompt & get the score for assignment3
Prompt & get the score for exam1
Prompt & get the score for exam2
weightedScore = (assignment1 + assignment2 +
assignment3) * 0.1 + (exam1 + exam2) * .35
output weightedScore
Activities
• Drive car or take DART bus?
• Party or study?
• Fly or drive?
What is the common idea for all these activities?
Programming problem:
using decision structure
Get hourly pay rate & # of hours, compute the
weekly pay, but do not pay for hours beyond
50.
Sample inputs:
Input:
Pay Rate
150
Input:
Hours
30
Output
150
60
Rs. 7500
Rs. 4500
Pseudocode
Prompt & get hourly pay rate & # of hours
IF hours <= 50
pay = hours * payRate;
ELSE
pay = 50 * payRate;
ENDIF
output pay
C code
Prompt & get hourly pay rate & # of hours
if (hours <= 50)
pay = hours * payRate;
else
pay = 50 * payRate;
output pay
Programming problem:
using decision structure
V2: Get hourly pay rate & # of hours, compute
the weekly pay, but do not pay for >50 hours.
Also, pay 1.5 times regular pay for overtime
hours (that is, # of hours beyond regular 40
hours).
First 40 hours: payRate
Next 10 hours: payRate * 1.5
Beyond 50 hours: 0
pseudocode
IF hours <= 40
pay = payRate * hours;
ELSE IF hours <= 50
pay = payRate * 40 + payRate * 1.5 * (hours – 40);
ELSE
pay = payRate * 40 + payRate * 1.5 * 10;
pseudocode #2
overHours = hours – 40;
IF hours <= 40
pay = payRate * hours;
ELSE IF hours <= 50
pay = payRate * 40 + payRate * 1.5 * overHours;
ELSE
pay = payRate * 40 + payRate * 1.5 * 10;
pseudocode #3
hours = (hours > 50 ? 50 : hours);
IF hours <= 40
pay = payRate * hours;
ELSE
pay = payRate * 40 + payRate * 1.5 * (hours – 40);
pseudocode #4
hours = (hours > 50 ? 50 : hours);
IF hours <= 40
pay = payRate * hours;
ELSE
basePay = payRate * 40;
overPay = payRate * 1.5 * (hours – 40);
pay = basePay + overPay;
Activities
• Bring in tons of purchased items from car to
house
• Load up uhaul truck when cleaning up
apartment
• Eat cookies from a box
• Taking an exam that has several questions
What is the common idea for all these activities?
Programming problem:
Using repetition structure
Compute the average score for the whole class.
Are we ready to code it?
Guessing game
• Guess a number between 1 and 100 in your
mind. Write a program so that the computer will
ask you a series of questions and determine that
number based on your answers.
Repeat the following steps as many times as
needed:
• Computer asks, “Is it NN?”
• User responds with <, =, or >
Pseudocode
Range – 2 variables: low = 1 and high = 100
• compute mid = (low + high) / 2
• Ask the user: Is it mid?
• Get user response
• adjust low or high based on response
• repeat as needed
Detailed pseudocode
Initialize range – 2 variables: low = 1 and high = 100
do {
compute mid = (low + high) / 2
Ask the user: Is it mid?
Get user response
if (response == ‘<‘)
high = mid-1;
else if (response == ‘>’)
low = mid+1;
while (response != ‘=‘);
Are we ready to code it?
Are we ready to code it?
• Google for “Java random number generation”
Guessing game V2 – Role reversal
• Let the computer guess a number between 1
and 100. Write a program so that the
computer will answer a series of your
questions and you will determine the number
based on computer’s responses.
Pseudocode
• Generate a random number between 0 and
100: assign rand() % 101 to a variable.
• then enter the loop
– get a guess from the user
– output <, >, or =
repeat until user enters =
Are we ready to code it?
• How to make the computer guess a number?
Summary
• All programs have only 3 control structures:
Sequence, decision & repetition
• Problem description  High level idea 
Detailed Pseudocode  Implement in specific
language  Executable program
C++ strings
• Similar functionality to hangman game
• Write a method to return # of tries to guess all
the letters in a given word.
• Sample run:
Guess the letters in *******:
s
letters in s******:
Pseudocode for guessWord()
• bool guessed[100];  initialize to false using loop
• int exposedCount = 0;
• int len = word.length();
for(int i = 0; i < len ; i++)
guessed[i] = false;
do {
for(int i = 0; i < len ; i++)
cout << (guessed[i] ? word[i] : “*”);
include code for getting next guess from the user
and updating guessed[] array and exposedCount.
} while (exposedCount < len);