#import <Foundation/Foundation.h>

@interface Expanditure : NSObject{
    double _breakfast;//早餐
    double _lauch;//中餐
    double _dinner;//晚餐
    double _count;//总消费
    double _average;//平均
}

-(void)setBreakfast:(double)breakfast;
-(double)getBreakfast;

-(void)setLauch:(double)lauch;
-(double)getLauch;

-(void)setDinner:(double)dinner;
-(double)getDinner;

-(double)getAverage;

@end

@implementation Expanditure

-(void)setBreakfast:(double)breakfast{
    _breakfast=breakfast;
    _count=0;//这个也必须要有,不然会重复计算
    _count=_breakfast+_lauch+_dinner;
   
    //如果调用者调用两次会出现重复.不行
   // _count+=_breakfast;
   
}
-(double)getBreakfast{
    return _breakfast;
   
}

-(void)setLauch:(double)lauch{
    _lauch=lauch;
    _count=0;
    _count=_breakfast+_lauch+_dinner;

   
}
-(double)getLauch{
    return _lauch;
   
}

-(void)setDinner:(double)dinner{
    _dinner=dinner;
    _count=0;
    _count=_breakfast+_lauch+_dinner;

   
}
-(double)getDinner{
    return _dinner;
   
}

-(double)getAverage{

    _average=_count/3;
    return _average;
   
}

@end

int main(){
   
    Expanditure *ed=[Expanditure new];
    [ed setBreakfast:100.0];
    [ed setLauch:600.0];
    [ed setDinner: 200.0];

    NSLog(@"今天的三餐的平均消费是:%f",[ed getAverage]);
    return 0;
}

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