Difference between revisions of "CSC231 Homework 3"
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==Problem #2== | ==Problem #2== | ||
| − | Assume that we want to compute the Fibonacci series with a compiled program. | + | Assume that we want to compute the [http://en.wikipedia.org/wiki/Fibonacci_number Fibonacci] series with a compiled program. |
| − | How many terms can we display if we use unsigned chars (8 bits) to store the Fibonacci terms? | + | * How many terms can we correctly display if we use unsigned chars (8 bits) to store the Fibonacci terms? |
| − | How many terms if we use unsigned short ints (16 bits)? | + | * How many terms if we use unsigned short ints (16 bits)? |
| − | How many terms if we use usigned ints (32 bits)? | + | * How many terms if we use usigned ints (32 bits)? |
| − | How many terms if we use long unsigned ints of 64 bits? | + | * How many terms if we use long unsigned ints of 64 bits? |
Explain carefully how you derive your answers. Prefered answers are answers that contain a program (in the language of your choice) demonstrating/illustrating in one way or another the answers to the various questions. | Explain carefully how you derive your answers. Prefered answers are answers that contain a program (in the language of your choice) demonstrating/illustrating in one way or another the answers to the various questions. | ||
| Line 78: | Line 78: | ||
==Problem #3== | ==Problem #3== | ||
| − | + | Assume that we write a C or C++ program that displays all the powers of 2 in this fashion: | |
| + | |||
| + | <code><pre> | ||
| + | |||
| + | unsigned int x = 1; | ||
| + | |||
| + | while ( x ) { | ||
| + | printf ( "%d\n", x ); | ||
| + | x = x * 2; | ||
| + | } | ||
| + | |||
| + | </pre></code> | ||
| + | |||
| + | * Is the loop infinite? Why? | ||
| + | |||
| + | * If it is not infinite, how many times does it go through, and how many terms does it print? Why? What is the last number displayed? | ||
| + | |||
| + | |||
| + | Store the answers to all 3 problems in a file called '''hw3.txt''' and submit it as follows: | ||
| + | |||
| + | submit hw3 hw3.txt | ||
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Assignment #3
This assignment is due on Wednesday Oct. 1st, at 11:59 p.m. plus one minute.
Problem #1
Same problem as we did in class. Below is the mystery program. Its output is listed in the header of the program.
/* mystery.cpp
// D. T.
// mystery program
// To compile and run this program:
//
// g++ mystery.cpp
// a.out
//
// The output of the program is the following
//
// 27001
// -31534
//
// With what positive values were x and y initialized
// at the beginning of the program. Explain why.
// (a short int contains 16 bits)
*/
#include <stdio.h>
main() {
short int x = ?????;
short int y = ?????;
x = x+y;
printf( "%d\n", x );
x = x+y;
printf( "%d\n", x );
}
What two positive numbers are stored in x and y to create the output listed in the header?
Explain your answer.
Problem #2
Assume that we want to compute the Fibonacci series with a compiled program.
- How many terms can we correctly display if we use unsigned chars (8 bits) to store the Fibonacci terms?
- How many terms if we use unsigned short ints (16 bits)?
- How many terms if we use usigned ints (32 bits)?
- How many terms if we use long unsigned ints of 64 bits?
Explain carefully how you derive your answers. Prefered answers are answers that contain a program (in the language of your choice) demonstrating/illustrating in one way or another the answers to the various questions.
Problem #3
Assume that we write a C or C++ program that displays all the powers of 2 in this fashion:
unsigned int x = 1;
while ( x ) {
printf ( "%d\n", x );
x = x * 2;
}
- Is the loop infinite? Why?
- If it is not infinite, how many times does it go through, and how many terms does it print? Why? What is the last number displayed?
Store the answers to all 3 problems in a file called hw3.txt and submit it as follows:
submit hw3 hw3.txt
