CSRU 1600 Computer Science 1 Summer 2009 Review Questions (Midterm) 2.2) State whether each of the following is true or false. If false, explain why.

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1 CSRU 1600 Computer Science 1 Summer 2009 Review Questions (Midterm) Chapter 2 2.1) Fill in the blanks in each of the following. a) Every C++ program begins execution at the function. b) A begins the body of every function and a ends the body. c) Every C++ statement ends with a(n). d) The statement is used to make decisions. 2.2) State whether each of the following is true or false. If false, explain why. a) Comments cause the computer to print the text after the // on the screen when the program is executed. b) The escape sequence \n, when output with cout and the stream insertion operator, causes the cursor to position to the beginning of the next line on the screen. c) All variables must be declared before they are used. d) All variables must be given a type when they are declared. e) C++ considers the variables number and NuMbEr to be identical. f) Declarations can appear almost anywhere in the body of a C++ function. g) The modulus operator (%) can be used only with integer operands. h) The arithmetic operators *, /, %, + and all have the same level of precedence. 2.3) Write a statement (or comment) to accomplish each of the following (assume that declarations have been used): a) Declare the variables x, y, z and result to be of type int (in separate statements). b) Prompt the user to enter three integers. c) Read three integers from the keyboard and store them in the variables x, y and z. d) Compute the product of the three integers contained in variables x, y and z, and assign the result to the variable result. e) Print "The product is " followed by the value of the variable result. f) Return a value from main indicating that the program terminated successfully.

2 2.4) Identify and correct the errors in each of the following statements (assume that the statement using std::cout; is used): a) if ( c < 7 ); cout << "c is less than 7\n"; b) if ( c => 7 ) cout << "c is equal to or greater than 7\n"; Chapter 3 3.1) Fill in the blanks in each of the following: a) A house is to a blueprint as a(n) is to a class. b) Every class definition contains the keyword followed immediately by the class s name. c) Each parameter in a function header must specify both a(n) and a(n). d) When each object of a class maintains its own copy of an attribute, the variable that represents the attribute is also known as a(n). e) Keyword public is a(n). f) Return type indicates that a function will perform a task but will not return any information when it completes its task. 3.2) What is the difference between a local variable and a data member? 3.3) Explain the purpose of a function parameter. What is the difference between a parameter and an argument? 3.4) Explain the difference between a function prototype and a function definition. 3.5) What is a default constructor? How are an object s data members initialized if a class has only an implicitly defined default constructor? 3.6) Explain why a class might provide a set function and a get function for a data member. Chapter 4 4.1) Write C++ statements to accomplish each of the following: a) In one statement, assign the sum of the current value of x and y to z and postincrement the value of x. b) Determine whether the value of the variable count is greater than 10. If it is, print "Count is greater than 10." c) Predecrement the variable x by 1, then subtract it from the variable total. d) Calculate the remainder after q is divided by divisor and assign the result to q. Write this statement two different ways.

3 4.2) State the values of each variable after the calculation is performed. Assume that, when each statement begins executing, all variables have the integer value 5. a) product *= x++; b) quotient /= ++x; 4.3) Identify and correct the errors in each of the following: a) while ( c <= 5 ) product *= c; c++; b) cin << value; c) if ( gender == 1 ) cout << "Woman" << endl; else; cout << "Man" << endl; d) if ( age >= 65 ); cout << "Age is greater than or equal to 65" << endl; else cout << "Age is less than 65 << endl"; e) int x = 1, total; while ( x <= 10 ) total += x; ++x; 4.4) What does the following program print? 1 // Exercise 4.12 Solution: ex04_12.cpp 2 // What does this program print? 3 #include <iostream> 4 using std::cout; 5 using std::endl; 6 7 int main() 8 9 int y; // declare y 10 int x = 1; // initialize x 11 int total = 0; // initialize total while ( x <= 10 ) // loop 10 times y = x * x; // perform calculation 16 cout << y << endl; // output result 17 total += y; // add y to total 18 ++x; // increment counter x 19 // end while cout << "Total is " << total << endl; // display result 22 return 0; // indicate successful termination 23 // end main Chapter 5 5.1) State whether the following are true or false. If the answer is false, explain why. a) The default case is required in the switch selection statement. b) The break statement is required in the default case of a switch selection statement to exit the switch properly. c) The expression ( x > y && a < b ) is true if either the expression x > y is true or the expression a < b is true.

4 d) An expression containing the operator is true if either or both of its operands are true. 5.2) Write a C++ statement or a set of C++ statements to accomplish the following: Sum the odd integers between 1 and 99 using a for statement. Assume the integer variables sum and count have been declared. 5.3) Find the error(s), if any, in each of the following code segments and explain how to correct it (them). a) x = 1; while ( x <= 10 ); x++; b) switch ( n ) case 1: cout << "The number is 1" << endl; case 2: cout << "The number is 2" << endl; break; default: cout << "The number is not 1 or 2" << endl; break; c) The following code should print the values 1 to 10. n = 1; while ( n < 10 ) cout << n++ << endl; Chapter 6 6.1) Answer each of the following: a) A function is invoked with a(n). b) A variable that is known only within the function in which it is defined is called a(n). c) The statement in a called function passes the value of an expression back to the calling function. d) The keyword is used in a function header to indicate that a function does not return a value or to indicate that a function contains no parameters. e) The of an identifier is the portion of the program in which the identifier can be used. f) A(n) allows the compiler to check the number, types and order of the arguments passed to a function. g) Variables declared in a block or in the parameter list of a function are assumed to be of storage class unless specified otherwise. h) Storage-class specifier is a recommendation to the compiler to store a variable in one of the computer s registers. i) A variable declared outside any block or function is a(n) variable. j) For a local variable in a function to retain its value between calls to the function, it must be declared with the storage-class specifier. k) A function that calls itself either directly or indirectly (i.e., through another function) is a(n) function.

5 l) A recursive function typically has two components one that provides a means for the recursion to terminate by testing for a(n) case and one that expresses the problem as a recursive call for a slightly simpler problem than the original call. m) It is possible to have various functions with the same name that operate on different types or numbers of arguments. This is called function. n) The enables access to a global variable with the same name as a variable in the current scope. o) The qualifier is used to declare read-only variables. p) A function enables a single function to be defined to perform a task on many different data types. 6.2) Find the error(s) in each of the following program segments, and explain how the error(s) can be corrected: a) int g() cout << "Inside function g" << endl; int h() cout << "Inside function h" << endl; b) int sum( int x, int y ) int result; result = x + y; c) int sum( int n ) if ( n == 0 ) return 0; else n + sum( n - 1 ); d) void f( double a ); float a; cout << a << endl; e) void product() int a; int b; int c; int result; cout << "Enter three integers: "; cin >> a >> b >> c; result = a * b * c; cout << "Result is " << result; return result; 6.3) Why would a function prototype contain a parameter type declaration such as double &?