Objective-C Programming (Sixth Edition) Chapter 4 answers to exercises

1. Invalid constant

0X10.5 0x0g1 98.7u 17777 s 0996 1.2Fe-7 15,000.

2.

// only need to list expressions can
        
         int F = 27; // F is set Fahrenheit, assignment 27
         float C; // set of floating type C to degrees Celsius, type
        
         C = (F-32) /1.8;
         NSLog (@ "% 1f.", C); //% .1f to one decimal place can

      // output
        2014-09-17 14: 58: 48.259 prog1 [6058: 303] -2.8
        Program ended with exit code: 0

3. The output result is D.

4.

float x = 2.55, result;
        
         result = 3 * (x * x * x) - 5 * (x * x) + 6;
        
         NSLog (@ "result is% f", result);

        // The result is as follows
       2014-09-17 15: 11: 11.064 prog1 [6196: 303] result is 23.231621

5.

// This question does not know what the test is listed expression had passed

         double result;
        
         result = (3.31e-8 + 2.01e-7) / (7.16e-6 + 2.01e-8);
        
         NSLog (@ "result is% e", result);
        
         // output
         2014-09-17 15: 29: 31.547 prog1 [6274: 303] result is 3.260400

6.

// ------------- Interface part -----------

@interface Complex: NSObject

- (void) setReal: (double) a; // set real number
- (void) setImaginary: (double) b; // set the imaginary
- (void) print; // print results
-(double) real;
-(double) imaginary;

@end

// -------------- implementation part ----------------

@implementation Complex
{
    double real;
    double imaginary;
}

- (void) setReal: (double) a
{
    real = a;
}

- (void) setImaginary: (double) b
{
    imaginary = b;
}

- (void) print
{
    NSLog (@ "The complex is% .f +% .fi", real, imaginary);
}

- (double) real
{
    return real;
}

- (double) imaginary
{
    return imaginary;
}


@end


// ---------------- program part -------------

int main (int argc, const char * argv [])
{

    @autoreleasepool {

        Complex * newComplex = [[Complex alloc] init];
        
        [newComplex setReal: 11];
        [newComplex setImaginary: 22];

// The following two methods can be, respectively, and the test print method real, imaginary methods; (subject to be required)
        [newComplex print];
  // NSLog (@ "The complex is% .f +% .fi", [newComplex real], [newComplex imaginary]);

       
    }
    return 0;
}

// The result is as follows
   2014-09-17 17: 27: 59.830 prog1 [6678: 303] The complex is 11 + 22i
   Program ended with exit code: 0 

7.

Mobile phone problems get mobile phone first

 

Objective-C Programming (Sixth Edition) Chapter 4 answers to exercises