C++学习--点滴记录003

「爱情、让人受尽委屈。」 2023-09-28 09:16 47阅读 0赞

## 3 运算符 ##

**作用：** 用于执行代码的运算

<table> 
 <thead> 
  <tr> 
   <th><strong>运算符类型</strong></th> 
   <th><strong>作用</strong></th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>算术运算符</td> 
   <td>处理四则运算</td> 
  </tr> 
  <tr> 
   <td>赋值运算符</td> 
   <td>将表达式的值赋给变量</td> 
  </tr> 
  <tr> 
   <td>比较运算符</td> 
   <td>表达式的比较，并返回一个真值或假值</td> 
  </tr> 
  <tr> 
   <td>逻辑运算符</td> 
   <td>根据表达式的值返回真值或假值</td> 
  </tr> 
 </tbody> 
</table>

### 3.1 算术运算符 ###

**作用：** 用于处理四则运算

**示例-加减乘除：**

#include<iostream>
    using namespace std;
    
    int main() {
        
    
    	int a1 = 10;
    	int b1 = 3;
    
    	cout << a1 + b1 << endl;
    	cout << a1 - b1 << endl;
    	cout << a1 * b1 << endl;
    	cout << a1 / b1 << endl;
    
    	int a2 = 10;
    	int b2 = 20;
    	cout << a2 / b2 << endl;
    
    	double c1 = 0.5;
    	double c2 = 0.25;
    	cout << c1 / c2 << endl;
    
    	system("pause");
    
    	return 0;
    }

![在这里插入图片描述][4f05a37739f64fbbb45841acfa70edb3.png_pic_center]

**示例-取模：**

#include<iostream>
    using namespace std;
    
    int main() {
        
    
    	int a1 = 10;
    	int b1 = 3;
    
    	cout << 10 % 3 << endl;
    
    	int a2 = 10;
    	int b2 = 20;
    
    	cout << a2 % b2 << endl;
    	system("pause");
    
    	return 0;
    }

![在这里插入图片描述][da74b1cdbd7d4037a567cee2fc096ad3.png_pic_center]  
**示例-递增：**

#include<iostream>
    using namespace std;
    
    int main() {
        
    
    	//后置递增
    	int a = 10;
    	a++; //等价于a = a + 1
    	cout << a << endl; 
    
    	//前置递增
    	int b = 10;
    	++b;
    	cout << b << endl; 
    
    	//区别
    	//前置递增先对变量进行++，再计算表达式
    	int a2 = 10;
    	int b2 = ++a2 * 10;
    	cout << b2 << endl;
    
    	//后置递增先计算表达式，后对变量进行++
    	int a3 = 10;
    	int b3 = a3++ * 10;
    	cout << b3 << endl;
    
    	system("pause");
    
    	return 0;
    }

![在这里插入图片描述][a61fa7f09a884466be7343ad7b4cfeab.png_pic_center]

**示例-递减：**

#include<iostream>
    using namespace std;
    
    int main() {
        
    
    	//后置递减
    	int a = 10;
    	a--; //等价于a = a - 1
    	cout << a << endl; 
    
    	//前置递减
    	int b = 10;
    	--b;
    	cout << b << endl; 
    
    	//区别
    	//前置递减先对变量进行--，再计算表达式
    	int a2 = 10;
    	int b2 = --a2 * 10;
    	cout << b2 << endl;
    
    	//后置递减先计算表达式，后对变量进行--
    	int a3 = 10;
    	int b3 = a3-- * 10;
    	cout << b3 << endl;
    
    	system("pause");
    
    	return 0;
    }

![在这里插入图片描述][37f8537bff784862a3341d25c04f7e13.png_pic_center]

### 3.2 赋值运算符 ###

**作用：** 用于将表达式的值赋给变量

**示例：**

#include<iostream>
    using namespace std;
    
    int main() {
        
    
    	int a = 10;
    	a = 100;
    	cout << "a = " << a << endl;
    
    	a = 10;
    	a += 2; // a = a + 2;
    	cout << "a = " << a << endl;
    
    	a = 10;
    	a -= 2; // a = a - 2
    	cout << "a = " << a << endl;
    
    	a = 10;
    	a *= 2; // a = a * 2
    	cout << "a = " << a << endl;
    
    	a = 10;
    	a /= 2;  // a = a / 2;
    	cout << "a = " << a << endl;
    
    	a = 10;
    	a %= 2;  // a = a % 2;
    	cout << "a = " << a << endl;
    
    	system("pause");
    
    	return 0;
    }

![在这里插入图片描述][4b9e0fff4e444f13bab8c1fd70edaa3a.png_pic_center]

### 3.3 比较运算符 ###

**作用：** 用于表达式的比较，并返回一个真值或假值

**示例：**

#include<iostream>
    using namespace std;
    int main() {
        
    
    	int a = 10;
    	int b = 20;
    
    	cout << (a == b) << endl;
    
    	cout << (a != b) << endl; 
    
    	cout << (a > b) << endl; 
    
    	cout << (a < b) << endl;
    
    	cout << (a >= b) << endl;
    
    	cout << (a <= b) << endl; 
    	
    	system("pause");
    
    	return 0;
    }

![在这里插入图片描述][61930f4939db44aa917263e1dec3259f.png_pic_center]

### 3.4 逻辑运算符 ###

**作用：** 用于根据表达式的值返回真值或假值

<table> 
 <thead> 
  <tr> 
   <th><strong>运算符</strong></th> 
   <th><strong>术语</strong></th> 
   <th><strong>示例</strong></th> 
   <th><strong>结果</strong></th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>!</td> 
   <td>非</td> 
   <td>!a</td> 
   <td>如果a为假，则!a为真； 如果a为真，则!a为假。</td> 
  </tr> 
  <tr> 
   <td>&amp;&amp;</td> 
   <td>与</td> 
   <td>a &amp;&amp; b</td> 
   <td>如果a和b都为真，则结果为真，否则为假。</td> 
  </tr> 
  <tr> 
   <td>||</td> 
   <td>或</td> 
   <td>a || b</td> 
   <td>如果a和b有一个为真，则结果为真，二者都为假时，结果为假。</td> 
  </tr> 
 </tbody> 
</table>

**示例-逻辑非：**

#include<iostream>
    using namespace std;
    int main() {
        
    
    	int a = 10;
    
    	cout << !a << endl; 
    
    	cout << !!a << endl; 
    
    	system("pause");
    	return 0;
    }

![在这里插入图片描述][7c85bcc4d5174a5e86eb798dceaaf78a.png_pic_center]  
**示例-逻辑与：**

#include<iostream>
    using namespace std;
    int main() {
        
    
    	int a = 10;
    	int b = 10;
    
    	cout << (a && b) << endl;
    
    	a = 10;
    	b = 0;
    
    	cout << (a && b) << endl;
    
    	a = 0;
    	b = 0;
    
    	cout << (a && b) << endl;
    
    	system("pause");
    	return 0;
    }

![在这里插入图片描述][d7b4494e6fd44465b08f748cd063c659.png_pic_center]  
**示例-逻辑或：**

#include<iostream>
    using namespace std;
    int main() {
        
    
    	int a = 10;
    	int b = 10;
    
    	cout << (a || b) << endl;
    
    	a = 10;
    	b = 0;
    
    	cout << (a || b) << endl;
    
    	a = 0;
    	b = 0;
    
    	cout << (a || b) << endl;
    
    	system("pause");
    	return 0;
    }

![在这里插入图片描述][5ab06b8349294fbdb11a03efeb96c37f.png_pic_center]  
**希望本文对大家有帮助，上文若有不妥之处，欢迎指正**

**分享决定高度，学习拉开差距**

[4f05a37739f64fbbb45841acfa70edb3.png_pic_center]: https://img-blog.csdnimg.cn/4f05a37739f64fbbb45841acfa70edb3.png#pic_center
[da74b1cdbd7d4037a567cee2fc096ad3.png_pic_center]: https://img-blog.csdnimg.cn/da74b1cdbd7d4037a567cee2fc096ad3.png#pic_center
[a61fa7f09a884466be7343ad7b4cfeab.png_pic_center]: https://img-blog.csdnimg.cn/a61fa7f09a884466be7343ad7b4cfeab.png#pic_center
[37f8537bff784862a3341d25c04f7e13.png_pic_center]: https://img-blog.csdnimg.cn/37f8537bff784862a3341d25c04f7e13.png#pic_center
[4b9e0fff4e444f13bab8c1fd70edaa3a.png_pic_center]: https://img-blog.csdnimg.cn/4b9e0fff4e444f13bab8c1fd70edaa3a.png#pic_center
[61930f4939db44aa917263e1dec3259f.png_pic_center]: https://img-blog.csdnimg.cn/61930f4939db44aa917263e1dec3259f.png#pic_center
[7c85bcc4d5174a5e86eb798dceaaf78a.png_pic_center]: https://img-blog.csdnimg.cn/7c85bcc4d5174a5e86eb798dceaaf78a.png#pic_center
[d7b4494e6fd44465b08f748cd063c659.png_pic_center]: https://img-blog.csdnimg.cn/d7b4494e6fd44465b08f748cd063c659.png#pic_center
[5ab06b8349294fbdb11a03efeb96c37f.png_pic_center]: https://img-blog.csdnimg.cn/5ab06b8349294fbdb11a03efeb96c37f.png#pic_center