CS50 Week 1

Question 0

What is the Linux command to show the content of a directory?

Answer 0

ls

Stands for list

Question 1

The format of an if condition

Answer 1

if (x > y)
{
     printf("x is less than y\n");
}
else if (x > y)
{
     printf("x is greater than y\n");
}
else
{
     printf("x is equal to y\n");

Question 2

What is the Linux command to create a new folder?

Answer 2

mkdir

Make directory

Question 3

What is the Linux command to change the directory?

Answer 3

cd

Question 4

What is the Linux command to delete a file?

Answer 4

rm

Question 5

What is the Linux command to delete a directory?

Answer 5

rmdir

Question 7

What indicates a new line?

Answer 7

\n

Question 8

What is the format of a while loop?

Answer 8

while ()
{
printf(“blah\n”)
}

Question 9

What function will get a string?

Answer 9

GetString()

Question 10

A line that starts with # is what?

Answer 10

A preprocessor directive

Question 11

What is the symbol for the boolean operator “or”?

Answer 11

||

Question 12

What is the symbol for the boolean operator “and”?

Answer 12

&&

Question 13

What is the syntax for a switch?

Answer 13

switch (x)
{
    case 1:
        // do this
        break;

    case 2:
        // do that
        break;

    default:
        // do this other thing
        break;
}

Question 14

What is the syntax of a for loop?

Answer 14

for (initializations; condition; updates)
{
    // do this again and again
}

Question 15

What is the syntax for a while loop?

Answer 15

while (true) {
print(“hello, world\n”);
}

Question 16

What is the syntax for a do/while loop

Answer 16

do
{
    // do this again and again
}
while (condition);

Question 17

How do we get a character from the user?

Answer 17

GetChar

Question 18

How do we get a double from the user?

Answer 18

GetDouble

Question 19

How do we get a float from the user?

Answer 19

GetFloat

Question 20

How do we get an int from the user?

Answer 20

GetInt

Question 21

How do we get a longlong from the user?

Answer 21

GetLongLong

Question 22

What data types does C not contain natively?

Answer 22

bool

string

Question 23

What are the types of C variables?

Answer 23

char
float
double
int
long long

Question 24

What is the printf formatting character for char?

Answer 24

%c

Question 25

What is the printf formatting character for an int?

Answer 25

%i

or %d

Question 26

What is the printf formatting character for a float?

Answer 26

%f

Question 27

What is the printf formatting character for a long long?

Answer 27

%lld

Question 28

What is the printf formatting character for a string?

Answer 28

%s

Question 29

What is the escape sequence for newline?

Answer 29

\n

Question 30

What is the escape sequence for carriage return?

Answer 30

\r

Question 31

What is the escape sequence for a single quote?

Answer 31

'

Question 32

What is the escape sequence for a double quote?

Answer 32

"

Question 33

What is the escape sequence for a backslash?

Answer 33

\

Question 34

What is the escape sequence for a null terminator?

Answer 34

\0