60-140-01 Fall 2009 Final Exam Preparation
|
Final Exam Date (covers materials from
chs. 1 – 9), lecture slides 1 – 225. Minus binary search
and sorting techniques and records. |
Saturday,
Dec. 12, 2009 Time: 8:30 – 11:30am. Where: ED 1101 (for section 60-140-01) |
|
Tentative Exam Viewing Date |
Monday, Dec.
14 (10:00am – 4:00pm in ER 2139) |
*** GOOD
LUCK ****
NOTE: In the event you cannot write the exam due to
illness or some other emergency (medical note required for proof), call the CS
office or send email to me as soon as possible to inform. There is only one make-up exam for all, who
could not write final and that is on Friday, Jan. 8, 2010 (1:00 – 4:00pm in ER
1115).
We
hope to mount exam viewing sessions on Monday, Dec. 14 (10:00am – 4:00pm in ER 2139) subject to we, completing the marking. Viewing is as scheduled unless otherwise
announced).
Student
Name and id:________________________________________________
These questions are to help
with preparing for final exams. The
questions in the final exam practice on pp. 243 of text are also helpful. To prepare well, read through all of the lecture
slides and the notes you have been writing to ensure you feel comfortable with
the materials taught in the course.
Refer to the text part of the book when you want more information about
some concepts in the lecture slides.
Chapter 10 also provides a quick reference collection you can use to
refresh your memory before the exams. The key to success is good preparation
and confidence.
Format
of the final Exam: 7 short program/segment questions in section A and 1 full
multi-function question with arrays and parameters in section B.
Que 1. Management wants to
rank the four weeks in each month based on the patterns of attendance in its 5
departments using attendance data collected weekly for 4 weeks. The attendance
(0 to 10) of each department is the same as the number of its employee
attendance since each department has only 10 employees. The number of employees
in attendance in each department every week for 4 weeks is read. Your program should calculate:
1.
The average attendance achieved each week (0 to 10).
2.
The attendance rank of each week based on the
condition that attendance average that is less than 7 is of rank low, average
that is between 7 and 8 is of rank medium while average attendance that is greater
than 8 is of rank high.
3.
Print the week with the lowest average and rank as
well as its average.
Provide C program
solution using top-down design approach.
Strictly use two-dimensional and one-dimensional arrays.
Sample input and output data:
Dep1 Dep2 Dep3 Dep4
Dep5
Wk1 10 5 4 10 10
Wk2 8 10 5 9 5
Wk3 10 7 8 1 5
Wk4 10 9 6 7 9
Sample Output is:
Dep1 Dep2 Dep3 Dep4
Dep5 Weekly Average Weekly
Attend Rank
Wk1 10 5 4 10 10 7.8 medium
Wk2 8 10 5 9 5 7.4 medium
Wk3 10 7 8 1 5 6.2 low
Wk4 10 9 6 7 9 8.2 high
Week 3 has lowest attendance
of 6.2
Solution to Question 1:
#include <stdio.h>
#include <string.h>
/*declare function prototypes*/
void ReadD (int [][5], int, int);
void Calc(int [][5], float [], char [][10], float *, int *);
void printres(int [][5], float [], char [][10], float *, int *);
void main () {
int attend[4][5], numwk=4, numdept=5, lowestwk;
float weekave[5], lowestavg;
char weekrank[4][10];
ReadD (attend, numwk, numdept);
Calc(attend, weekave, weekrank, &lowestavg, &lowestwk);
printres(attend, weekave, weekrank, &lowestavg, &lowestwk);
}
/*read data into array of attend and numdemp*/
void ReadD (int attend[][5], int numwk, int numdept)
{
int r, c;
for
(r=0; r<numwk; r++) {
printf("Type 5 weekly attendance for 5 depts for week %d and hit enter\n", r);
for (c=0; c<5; c++){
scanf ("%d", &attend[r][c]);}
}
}
/*calculate rank averages and rating of each week */
void Calc(int attend[][5], float weekave[], char weekrank[][10], float *lowestavg, int *lowestwk)
{
int r, c, wksum[4]={0,0,0,0};
for (r = 0; r< 4; r++)
{
for (c = 0; c<5; c++)
{
wksum[r] += attend[r][c];
}
weekave[r]
= (float) wksum[r]/5;
if (weekave[r] < 7.0) strcpy(weekrank[r], "low");
else if (weekave[r] < 8.0) strcpy(weekrank[r], "medium");
else strcpy(weekrank[r], "high");
/* compute the lowest average and week */
if (r == 0) *lowestavg = weekave[r];
else if (weekave[r] < *lowestavg)
{
*lowestavg = weekave[r];
*lowestwk = r;
}
}
}
/*column calculation*/
void printres(int attend[][5], float weekave[], char weekrank[][10], float *lowestavg, int *lowestwk)
{
int r, c;
printf("\t
Dep1 \t Dep2 \t Dep3 \t Dep4 \t Dep5 \t Week Average \t Week Rank \n");
for (r=0; r<4; r++)
{
printf("Wk%d \t",r+1);
for (c = 0; c< 5; c++)
{
printf("%d\t ", attend[r][c]);
}
printf("%0.2f\t %s \n", weekave[r], weekrank[r]);
}
printf("Week %d has the lowest attendance of %0.2f \n", *lowestwk+1, *lowestavg);
} /* end of printres */
Que. 2. Write a short program that takes two 5-digit
integers and prints the five pairs of single digits belonging to these two
numbers starting with the leftmost (or most significant) digits.
Que 3: What is printed by
the following switch_case instruction?
int code = 2;
switch
(code) {
case 1 : printf(“First”);
case 2 :
printf(“Second”);
case 3 : printf(“Third”);
default :
printf(“All”);
}
Solution: SecondThirdAll
This is because it does not
break once it executes a switch case that matches.
Que. 4. The program below
should read a list of ages and compute the maximum age. The integer number 0 is a sentinel. There are some logic errors (three of them),
which cause the algorithm to work incorrectly.
Correct these errors.
#include
<stdio.h>
void main(void)
{
float Age, Maxi;
scanf (“%f”,
&Age);
Maxi = Age;
while (Age = 0) change to while (Age != 0)
{
if (Age > Maxi)
Age = Maxi; change to then Maxi = Age;
insert scanf
(“%f”, &Age);
}
printf ("Maximum age is: %f",
Maxi);
}
Solution: Answers already marked on the right sides of
the lines with errors. Remember to solve event control problems by ensuring
that all of their initialization, testing for termination, loop body processing
with updating of control variable are properly done.
Que. 5. Write
a short program to read lines of data
for each student consisting of studid, name, major, gpa from a disk data file
(called stnrec.txt) until end of file (and not from a key board) and print to
the monitor, lines of data read, number of data records read as well as the
minimum of all gpas read.
Solution:
#include <stdio.h>
void main (void)
{ FILE *stnptr; /* 1.
must declare file pointer variable */
char studentid[15], name[15], major[20];
float gpa, mingpa;
int k;
stnptr=fopen("stnrec.txt","r"); /* 2. must associate file pointer
variable with a disk file and
open for read */
k = 0;
fscanf (stnptr, "%s %s %s %f", studentid, name, major,
&gpa);
/*3.
must read from the file pointer variable
*/
while (!feof(stnptr)) /* test
for termination must indicate the file pointer
*/
{
printf ("%s \t %s \t %s
\t %0.2f \n", studentid, name, major, gpa);
if (k == 0) mingpa =
gpa;
else if (gpa
< mingpa) mingpa = gpa;
k++;
fscanf (stnptr,
"%s %s %s %f", studentid, name, major, &gpa);
/*3.
continuity read from file */
}
/* end of while */
printf("Number of records in file is %d\n", k);
printf("The minimum gpa is: %0.2f\n", mingpa);
fclose(stnprt); /*
4. must close the file */
} /* end of program */
Que. 6. The given table represents a multiplication
table. Write a program to produce it
using looping, without reading any data from the keyboard or file.
X 5 7 9 11
1 5 7 9 11
2 10 14 18 22
3 15 21 27 33
4 20 28 36 44
Que. 7. Given the following
list, write a short program to search this list for a 91 and which prints the
positon of the search key element if found and a message indicating it is not
there if not found. The input list is: 80
34 68 91 52.
Que. 8. Given the following program segments, write
two program segments to say the same thing, using (a) do-while instruction, and
(b) “for loop” instruction (c) show your tracing of these program segments.
N = 0;
while ( N
<= 10 )
{
N
++;
printf(“%d”,
N);
}
**********
A = 5;
while (A >= 1)
{
B = 1;
while (B >= 1)
{
printf
(“%d”, B);
B--;
}
printf (“\n”);
A--;
}
9. Write a program that will take one integer number followed
by an operator (% /), then followed by a second number. Your program should read the data and perform
the calculation and print the equation with result. Eg. If the input data is 10 / 4, output is
10 / 4 = 2.
10. Given three student names in the order lastname
firstname, write a C program to read these names and store them in an array and
print them nicely in a table.
11. Write a short program that prints the following
pattern using a double nested loop.
*
* * *
*
* * * *
* *
* * *
* *
Solution:
#include <stdio.h>
void main(void)
{
int row, col, nspace,
nstar;
for (row = 1; row <= 4; row++)
{
Nspace = 4 –
row;
Nstar =
(2 * row) – 1;
for (col = 1; col <= nspace; col ++)
{
printf (“ “);
}
for (col = 1; col <= nstar; col++)
{
printf (“*”);
}
printf (“\n”);
}
}
12. Given an array of 5 integer scores, write a C program to
read these scores and print both the input array, the minimum score and the maximum score.
Solution:
#include <stdio.h>
void main(void)
{
/* The simple program that finds
reads an array of 5 scores and
prints the minimum and maximum
scores.
Also, print the result with
input data in a table */
int mark[5], mini, maxi, knt;
/* initialization, testing */
knt = 0;
while(knt < 5)
{
printf("type the %d
mark \t:", knt);
scanf("%d",
&mark[knt]);
if (knt == 0)
{
mini = mark[0]; /* set the first as minimum */
maxi =
mark[0]; /* set the first as maximum*/
}
if (mark[knt] < mini)
mini = mark[knt];
else if
(mark[knt] > maxi)
maxi =
mark[knt];
knt++;
}
/* This now prints the input data
and result */
printf("Mark \n");
for (knt = 0; knt < 5; knt++)
{
printf("%d \n",
mark[knt]);
}
printf("minimum = %d
\n", mini);
printf("maximum = %d
\n", maxi);
}
13. Given three student names in the order lastname
firstname, write a C program to read these names a into an array and copy these
names into a second array and print the two string arrays where the first
student name in array1 is printed on the same line with the names of the last
student in the second array2, etc.
nicely in a table. E.g., if input
data are: Adams John, Cooks Mary, Black Tony, the output should look like:
FirstName1 LastName1 FirstName2 LastName2
John
Mary Cooks Mary Cooks
Tony Black John
Solution:
#include <stdio.h>
#include <string.h>
void main(void)
{
/* The simple program that
reads three student names
as lastname firstname into a pair of arrays,
called
firstName1, lastName1 and
copies the names into a
second pair of arrays
called firstName2, lastName2,
to print the first Names
in forward order while the
second names are printed in reverse order all
in a table */
int
r;
char firstname1[3][10], lastname1[3][10];
char firstname2[3][10], lastname2[3][10];
for (r= 0; r< 3; r++)
{
printf("please, type the %d lastname
firstname of input\n", r);
scanf("%s %s", lastname1[r],
firstname1[r]);
/* Now copy into second arrays */
strcpy(lastname2[r], lastname1[r]);
strcpy(firstname2[r], firstname1[r]);
}
printf("FirstName1 \t
LastName1 \t FirstName2 \t LastName2\n");
printf("**********************************************\n");
/* Now print the table of
results */
for (r=0; r<3; r++)
{
printf("%s \t \t %s
\t\t %s \t\t %s\n", firstname1[r], lastname1[r], firstname1[2-r], lastname1[2-r]);
}
}
**
We have covered and should know:
Chs 1 – 3: Assignment Instructions,
scanf
and printf instructions with data types,
function
definitions with formal parameters.
Parameters
can be either call-by-value or call-by-reference.
Results
computed by a function can be sent back through “return” instruction
or
changed directly using call-by-reference parameter.
A
function can use its formal parameters, local variables or global
variables.
nested
if-else instructions
-
negative
if logic (as in instructions of the format: if …if … else …else),
-
and
positive if logic (as in instructions of the format: if … else if … else …),
- as well as switch-case instructions.