Fraction类(分数)实现分数的加减乘除, ⽐比较⼤大⼩小、约分等⽅方法

Fraction.h:

#import <Foundation/Foundation.h>

@interface Fraction : NSObject

//声明两个实例变量

@property NSInteger upNumber, downNumber;

//自定义初始化方法

- (id)initWithUpNumber:(NSInteger)upNumber downNumber:(NSInteger)downNumber;

//便利构造器

+ (id)fractionWithUpNumber:(NSInteger)upNumber downNumber:(NSInteger)downNumber;

//求最大公约数

- (NSInteger)GCDNumber:(NSInteger)num1 number2:(NSInteger)num2;

//约分

- (void)reduce;

//加法

- (Fraction *)addFraction:(Fraction *)anotherFraction;

//减法

- (Fraction *)delFraction:(Fraction *)anotherFraction;

//乘法

- (Fraction *)mulFraction:(Fraction *)anotherFraction;

//除法

- (Fraction *)divFraction:(Fraction *)anotherFraction;

//比较大小

- (void)comFraction:(Fraction *)num1 ;

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Fraction.m:

#import "Fraction.h"

@implementation Fraction

- (id)initWithUpNumber:(NSInteger)upNumber downNumber:(NSInteger)downNumber {

    if (self = [super init]) {

        _upNumber = upNumber;

        _downNumber = downNumber;

    }

    return self;

}

+ (id)fractionWithUpNumber:(NSInteger)upNumber downNumber:(NSInteger)downNumber {

    return [[Fraction alloc] initWithUpNumber:upNumber downNumber:downNumber];

}

//重写方法

- (NSString *)description

{

    return [NSString stringWithFormat:@"%ld/%ld", _upNumber, _downNumber];

}

#pragma mark -运算方法

//求最大公约数

- (NSInteger)GCDNumber:(NSInteger)num1 number2:(NSInteger)num2 {

//利用辗转相除法, 求出最大公约数

        while (num2 != 0) {

        NSInteger temp = num1 % num2;

        num1 = num2;

        num2 = temp;

    }

    return num1;

}

//约分

- (void)reduce {

    NSInteger num = [self GCDNumber:_upNumber number2:_downNumber];

//分子, 分母都以最大公约数, 就是约分后的分子, 分母

    _upNumber /= num;

    _downNumber /= num;

}

//加法

- (Fraction *)addFraction:(Fraction *)anotherFraction {

    Fraction *fraction = [[Fraction alloc] init];

//两分数相加后的分子

    fraction.upNumber = _upNumber * anotherFraction.downNumber + anotherFraction.upNumber * _downNumber;

//相加后的分母

    fraction.downNumber = _downNumber * anotherFraction.downNumber;

    [fraction reduce];

    return fraction;

}

//减法

- (Fraction *)delFraction:(Fraction *)anotherFraction {

    Fraction *fraction = [[Fraction alloc] init];

//两分数相减后的分子

    fraction.upNumber = _upNumber * anotherFraction.downNumber - anotherFraction.upNumber * _downNumber;

//两分数相减后的分母

    fraction.downNumber = _downNumber * anotherFraction.downNumber;

    [fraction reduce];

    return fraction;

}

//乘法

- (Fraction *)mulFraction:(Fraction *)anotherFraction {

    Fraction *fraction = [[Fraction alloc] init];

//两分数相乘后的分子

    fraction.upNumber = _upNumber * anotherFraction.upNumber;

//两分数相乘后的分母

    fraction.downNumber = _downNumber * anotherFraction.downNumber;

    [fraction reduce];

    return fraction;

}

//除法

- (Fraction *)divFraction:(Fraction *)anotherFraction {

    Fraction *fraction = [[Fraction alloc] init];

//两分数相除后的分子

    fraction.upNumber = _upNumber * anotherFraction.downNumber;

//两分数相除后的分母

    fraction.downNumber = _downNumber * anotherFraction.upNumber;

    [fraction reduce];

    return fraction;

}

//比较大小

- (void)comFraction:(Fraction *)num1  {

    Fraction *result = [self delFraction:num1];

//比较两个分数的大小

    if (result == 0) {

        NSLog(@"两数相等!");

    }

    if (result > 0) {

        NSLog(@"%@ > %@", self, num1);

    }else if (result < 0) {

        NSLog(@"%@ < %@", self, num1);

    }

}

@end

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main:

#import <Foundation/Foundation.h>

#import "Fraction.h"

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

    @autoreleasepool {

        

//       创建⼀一个Fraction类(分数)实现分数的加减乘除,⽐比较⼤大⼩小、约分等⽅方法。

//       要求:为类添加属性

        Fraction *num1 = [[Fraction alloc] initWithUpNumber:4 downNumber:12];

        Fraction *num2 = [[Fraction alloc] initWithUpNumber:3 downNumber:12];

        //两分数之和

        Fraction *sum = [num1 addFraction:num2];

        NSLog(@"%@", sum);

        //两数之差

        Fraction *del = [num1 delFraction:num2];

        NSLog(@"%@", del);

        //两数之积

        Fraction *mul = [num1 mulFraction:num2];

        NSLog(@"%@", mul);

        //两数之商

        Fraction *div = [num1 divFraction:num2];

        NSLog(@"%@", div);

        //两数比较大小

        [num1 comFraction:num2];   

    }

    return 0;

}

运行结果: