CS 1044 Homework 2 Key
Spring 1999

 Q  Ans Reason
 1   B  12.0 / 5.0 + 2 / 5 == 2.4 + 0 == 2.4
        Note:  2 / 5 is done as int arithmetic.
 2   D  10 / 3 == 3 (int arithmetic), then multiply that by 5
 3   C  10 % 5 == 0 since 5 divides into 10 without a remainder;
        2 % 5 == 2 since 5 goes into 2 zero times, with a remainder of 2
 4   E  15 / 1.2 == 12.5
 5   B  5 / 2 == 0 (int division); assigning to a double makes it 2.0
 6   A  7.0 / 4.0 == 1.75; assigning to an int truncates the value to 1
 7   A  
 8   A  The caret symbol (^) actually IS a valid arithmetic operator in
        C++, representing the bitwise exclusive or.  But we haven't covered
        that yet, so you may have said it's invalid syntax.  Either A or B
        will be counted correct here.
 9   A  
10   B  You can't extract from the output stream.
11   D  cin >> anInt     // This extracts 1 into anInt
            >> aChar;    // This extracts the next character, '.' into aChar
12   B  cin >> aDble     // This extracts 1.2 into aDble
            >> aChar;    // This extracts '4' into aChar
13   B  cin >> aDble     // This extracts 1.2 into aDble
            >> anInt;    // This extracts 4 into anInt
14   B  cin >> anInt;    // This extracts 1 into anInt
        cin.get(aChar);  // This gets '.' and places it into aChar
        cin >> anInt;    // This extracts 2 into anInt
15   C  The expression 30 + 12 is evaluated, and its value is printed in
        a field that's 3 columns wide.
16   C  This is the only one that correctly groups a+b and d+e.
17   C  (4 + 8 + 5 + 4) / 4 == 21 / 4 == 5 (int division); assigning that
        to a double converts it to 5.0
18   D  
19   A  Direct from slide on operator precedence.
20   B  From class discussion, int and double values are stored in a different
        format, even if the values are (mathematically) the same.