Ch5. Exercise 8 Answer

[peakok]

Code: (Objective-C)

#import <Foundation/Foundation.h>



int main (int argc, const char * argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
	
	//Use long int to allow big numbers
	long int number, sum, originalNumber;
	
	// Ask the user to input a number
	NSLog(@"Enter a number to evaluate:");
	scanf("%li", &number);
	
	// Store the original number so that we can print it later
	originalNumber = number;
	
	//If the number is negative, make it positive
	if (number < 0) {
		number = ~number + 1;
	}
	
	//Perform the addition of all the digits
	sum = 0;
	while (number > 0) {
		sum += number % 10;    //Get the last digit 
		number = number / 10; 
	}
	
	//Announce the results
	NSLog(@"The result for the number %li is: %li", originalNumber, sum);
	
	
	[pool drain];
	return 0;
}

Running…
[37402:a0f] Enter a number to evaluate:
-4597524
[37402:a0f] The result for the number -4597524 is: 36