objective-c第七章答案

来源：互联网发布：淘宝服装模特拍摄编辑：程序博客网时间：2024/06/05 18:03

1， - (Fraction *) subtract: (Fraction *) f

解释：

{ Fraction * result = [[Fraction alloc] init];

        result.numerator = numerator * f.denominator - denominator * f.numerator;

        result.denominator = denominator * f.denominator;

        [result reduce];

        return result;

2,- (Fraction *) multiply: (Fraction *) f
解释；
{  Fraction * result = [[Fraction alloc] init];
      result.numerator =numerator * f.denominator;
      result.denominator = denominator *f.denominator;
      [result reduce];    return result;
}

- (Fraction *) subtract: (Fraction *) f 2 { 3     Fraction *result = [[Fraction alloc] init]; 4      5     result.numerator = numerator *f.denominator - denominator *f.numerator; 6     result.denominator = denominator *f.denominator; 7      8     [result reduce]; 9     return  result;10 }11 12 - (Fraction *) multiply: (Fraction *) f13 {14     Fraction *result = [[Fraction alloc] init];15     16     result.numerator = numerator *f.numerator;17     result.denominator = denominator *f.denominator;18     19     [result reduce];20     return result;21 }22 23 - (Fraction *) divide: (Fraction *) f24 {25     Fraction *result = [[Fraction alloc] init];26     27     result.numerator = numerator *f.denominator;28     result.denominator = denominator *f.numerator;29     30     [result reduce];31     return result;32 }
2.print方法
 1 - (void) print: (BOOL) isReduce 2 { 3     if (numerator % denominator == 0) { 4         NSLog(@"%d",numerator/denominator); 5     }else if (isReduce) { 6         [self reduce]; 7         NSLog(@"%d / %d",numerator,denominator); 8     }else 9         NSLog(@"%d / %d",numerator,denominator);10 11 }
3.对负分数一样使用
 1 int main(int argc, const char * argv[]) { 2     @autoreleasepool { 3         // insert code here... 4          5         Fraction *aFraction = [[Fraction alloc] init]; 6         Fraction *bFraction = [[Fraction alloc] init]; 7         Fraction *resultFraction; 8          9         [aFraction setTo:-1 over:4];10         [bFraction setTo:-1 over:2];11         12         resultFraction = [aFraction add:bFraction];13         14         15         [resultFraction print:YES];16     }17     return 0;18 }
4.
 1 - (void) print: (BOOL) isReduce  2 { 3     if (numerator % denominator == 0) { 4         NSLog(@"%d",numerator/denominator); 5     }else if (numerator > denominator){ 6         [self reduce]; 7         NSLog(@"%d %d/%d",numerator/denominator,numerator % denominator,denominator); 8     }else if (isReduce) { 9         [self reduce];10         NSLog(@"%d/%d",numerator,denominator);11     }else12         NSLog(@"%d/%d",numerator,denominator);13 14 }
5.去掉synthesize合成方法后 修改变量名 _numerator, _denominator  替换程序中的numerator,denominator;增加setter方法 用于点语法。
6..m文件
1 - (Complex *) add: (Complex *) complexNum2 {3     Complex *result = [[Complex alloc] init];4     5     result.real = real + complexNum.real;6     result.imaginary = imaginary + complexNum.imaginary;7     8     return result;9 }
main
 1         Complex * aComplex = [[Complex alloc]init]; 2         Complex * bComplex = [[Complex alloc]init]; 3         Complex * resultComplex; 4  5          6         [aComplex setReal:5.3]; 7         [aComplex setImaginary:7]; 8         [bComplex setReal:2.7]; 9         [bComplex setImaginary:4];10         resultComplex = [aComplex add:bComplex];11         12         NSLog(@"result is %.f + %.fi",[resultComplex real],[resultComplex imaginary]);13

0 0