Functions and Subroutines Questions

• C#.NET — Predict output using ref parameters to return square and cube. Program: namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { int a = 5; int s = 0, c = 0; Proc(a, ref s, ref c); Console.WriteLine(s + " " + c); } static void Proc(int x, ref int ss, ref int cc) { ss = x * x; cc = x * x * x; } } }
• C#.NET — Choose the correct method signature: receives (int, Single, double), returns decimal. Which definition is valid?
• C#.NET — Multiple return values via function: identify compile-time errors in call and return. Program: namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { int a = 5; int s = 0, c = 0; s, c = fun(a); Console.WriteLine(s + " " + c); } static int fun(int x) { int ss, cc; ss = x * x; cc = x * x * x; return ss, cc; } } } Which statements are correct?
• C#.NET — Determine the printed output for the following program (note: the loop intentionally iterates to Length - 1, so the last element is skipped): namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { object[] o = new object[] {"1", 4.0, "India", 'B'}; fun(o); } static void fun(params object[] obj) { for (int i = 0; i < obj.Length - 1; i++) Console.Write(obj[i] + " "); } } }
• C#.NET — What does the following program print (factorial computed via out parameter)? namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { int i; int res = fun(out i); Console.WriteLine(res); } static int fun(out int i) { int s = 1; i = 7; for (int j = 1; j <= i; j++) { s = s * j; } return s; } } }
• In C# terminology, how many values can a subroutine (a void method) effectively return?
• C# design: If a function sometimes receives an int and sometimes a double, which definition best supports both cases cleanly?
• True or False: A function returns a value, whereas a subroutine (void method) cannot return a value via the return keyword.
• True or False: A function can be used within an expression, whereas a subroutine (void method) cannot be used as an expression operand.
• C#.NET — What will the corrected program print? (Assume the intended method name is fun1, not funl.) namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { int i = 5; int j; fun1(ref i); fun2(out j); Console.WriteLine(i + ", " + j); } static void fun1(ref int x) { x = x * x; } static void fun2(out int x) { x = 6; x = x * x; } } }
• C#.NET — After fixing spacing in the array creation (new int[]), what does this program print? namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { int[] arr = new int[] { 1, 2, 3, 4, 5 }; fun(ref arr); } static void fun(ref int[] a) { for (int i = 0; i < a.Length; i++) { a[i] = a[i] * 5; Console.Write(a[i] + " "); } } } }
• C#.NET — Which of the following can occur only once per program (single entry point requirement)?
• In C#, how many values can a function return directly via its return value?
• C#.NET — Identify correct statements about functions (recursion, nesting, returns, and nested calls). Which of the following statements are correct about functions used in C#.NET? Function definitions cannot be nested. Functions can be called recursively. If we do not return a value from a function then a value -1 gets returned. To return the control from middle of a function, the keyword "exit function" should be used. Function calls can be nested.
• C#.NET — Choose the correct method declaration for: accepts (int, Single, double) and returns decimal. If a procedure fun() is to receive an int, a Single, and a double, and it must return a decimal, which of the following is the correct way to define it?
• C#.NET — Functions vs “subroutines” (void methods): ref behavior, recursion, and call rules. Which statements are correct about functions and subroutines used in C#.NET? A function cannot be called from a subroutine. The ref keyword causes arguments to be passed by reference. With ref, changes in the method are reflected back in the caller. A subroutine cannot be called from a function. Functions and subroutines can be called recursively.
• C#.NET — Defaults, variable-argument methods, and error types in definitions. Which statements are correct? C# allows a function to have arguments with default values. C# allows a function to have a variable number of arguments. Omitting the return value type in a method definition results in an exception. Redefining a method parameter inside the method body causes an exception. The params keyword specifies a variable number of arguments.
• C#.NET — Predict output with overload resolution and double formatting. Consider: namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { int i = 10; double d = 34.340; fun(i); fun(d); } static void fun(double d) { Console.WriteLine(d + " "); } } } What will be printed?
• C#.NET — Identify correct statements about void methods (“subroutines”): nesting, recursion, exit, and nested calls. Which statements are correct about subroutines used in C#.NET? If we do not return a value from a subroutine then a value -1 gets returned. Subroutine definitions cannot be nested. Subroutine can be called recursively. To return the control from the middle of a subroutine, use "exit subroutine". Subroutine calls can be nested.
• C#.NET — Trace pass-by-value vs pass-by-reference (ref) and predict the print sequence. Program: namespace CuriousTabConsoleApplication { class SampleProgram { static void Main(string[] args) { int num = 1; funcv(num); Console.Write(num + ", "); funcr(ref num); Console.Write(num + ", "); } static void funcv(int num) { num = num + 10; Console.Write(num + ", "); } static void funcr(ref int num) { num = num + 10; Console.Write(num + ", "); } } } What will be printed?