Stuart's Answer

[Hutch]

Code: (Objective-C)

#import <Foundation/Foundation.h>

@interface Accumulator : NSObject
{
	double accumulated;
}

-(void) add: (double) value;
-(void) subtract: (double) value;
-(void) multiply: (double) value;
-(void) divide: (double) value;
-(void) setAccumulator: (double) value;
-(double) accumulated;

@end

@implementation Accumulator

-(void) add: (double) value
{
	accumulated += value;
}

-(void) subtract: (double) value
{
	accumulated -= value;
}

-(void) multiply: (double) value
{
	accumulated *= value;
}

-(void) divide: (double) value
{
	accumulated /= value;
}
-(void) setAccumulator: (double) value
{
	accumulated = value;
}
-(double) accumulated
{
	return accumulated;
}

@end


int main (int argc, const char * argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
	
	Accumulator *myAccumulator = [[Accumulator alloc]init];
	char op;
	double number;
	
	scanf("%lf %c", &number, &op);
	
	while (op != 'E') {
		scanf("%lf %c", &number, &op);
			switch (op) {
				case '+':
					[myAccumulator add: number];					
					break;
					
				case '-':
					[myAccumulator subtract: number];
					break;
					
				case 'x':
				case 'X':
				case '*':
					[myAccumulator multiply: number];
					break;
					
				case '/':
					if (number == 0)
						NSLog(@"Can not divide by zero.");
					else 					
						[myAccumulator divide: number];
					break;
					
				case 's':
				case 'S':
					[myAccumulator setAccumulator: number];
					
					break;
					
				default:
					NSLog(@"Unknown operator.");
					break;
			}
		NSLog(@"= %g", [myAccumulator accumulated]);
	}
	NSLog(@"End of program");

	[myAccumulator release];
    [pool drain];
    return 0;
}

Thoughts on where I could improve?