4.12: Comparing Characters and String Objects

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is NOT a letter.

!((x >= 'A' && x <='Z') || (x >= 'a' && x <='z'))

Assume that c is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if c is NOT what is called a whitespace character (that is a space or a tab or a newline-- none of which result in ink being printed on paper).

!(c == ' ' || c== '\n' || c == '\t')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is NOT a upper-case letter.

!(x >= 'A' && x <='Z')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is an hexadecimal (Base 16) digit (0-9 plus A-F or a-f).

( ( x>='0' && x<='9') || ( x>='a' && x<='f' ) || ( x>='A' && x<='F') )

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is NOT a letter.

((x>='A' && x<='Z') || (x>='a' && x<='z'))

Assume that c is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if c is what is called a whitespace character (that is a space or a tab or a newline-- none of which result in ink being printed on paper).

(c == ' ' || c== '\n' || c == '\t')

Assume that c is a char variable that has been declared and already given a value . Write an expression whose value is true if (c == '\n')and only if c is an newline character .

(c == '\n')

Assume that c is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if c is a tab character .

(c=='\t')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is an octal (Base 8) digit (0-7).

(x>='0' && x<='7')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is a decimal digit (0-9).

(x>='0' && x<='9')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is a upper-case letter.

(x>='A' && x<='Z')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is a letter.

(x>='A' && x<='Z') || (x>='a' && x<='z')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is alphanumeric , that is either a letter or a decimal digit.

(x>='A' && x<='Z') || (x>='a' && x<='z') || (x>='0' && x<='9')

Assume that x is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if x is a lower-case letter.

(x>='a' && x<='z')

What's the difference in ASCII value between '3' and '0'? (consult a table of ASCII values):

3

What's the difference in ASCII value between 'E' and 'A'? (consult a table of ASCII values): http://www.asciitable.com

4

What's the difference in ASCII value between 'e' and 'a'? (consult a table of ASCII values):

4

What's the difference in ASCII value between '6' and '0'? (consult a table of ASCII values):

6

Assume that c is a char variable that has been declared and already given a value . Write an expression whose value is true if and only if c is a space character .

c == ' '

Assume that s is a string . Write an expression whose value is true if and only if the value of s would come between "mortgage" and "mortuary" in the dictionary.

s > "mortgage" && s < "mortuary"