运算符

运算符是一个符号，它告诉编译器执行特定的数学或逻辑函数。C语言具有丰富的内置运算符，并提供以下类型的运算符:

• Arithmetic Operators 算术运算符
• Comparison Operators 比较运算符
• Boolean Operators 布尔运算符
• Bitwise Operators 位运算符
• Compound Operators 复合运算符

  算术运算符

  假设变量A为10，变量B为20，则：

例子

void setup () {
Serial.begin(9600);

   int a = 9,b = 4,c;
   c = a + b;
   Serial.print("a + b=");
   Serial.println(c);
   c = a - b;
   Serial.print("a - b=");
   Serial.println(c);
   c = a * b;
   Serial.print("a * b=");
   Serial.println(c);
   c = a / b;
   Serial.print("a / b=");
   Serial.println(c);
   c = a % b;
   Serial.print("a% b=");
   Serial.println(c);

}

结果

a + b = 13
a - b = 5
a * b = 36
a / b = 2
a % b = 1

比较运算符
假设变量A为10，变量B为20，则：

例子

void setup () { 
   int a = 9,b = 4
   bool c = false;
   if(a == b)
      c = true;
   else
      c = false;

   if(a != b)
      c = true;
   else
      c = false;

   if(a < b)
      c = true;
   else
      c = false;

   if(a > b)
      c = true;
   else
      c = false;

   if(a <= b)
      c = true;
   else
      c = false;

   if(a >= b)
      c = true;
   else
      c = false;
}

结果

c = false
c = true
c = false
c = true
c = false
c = false

布尔运算符
假设变量A为10，变量B为20，则：

例子

void setup () {
   int a = 9,b = 4
   bool c = false;
   if((a > b)&& (b < a))
      c = true;
   else
      c = false;

   if((a == b)|| (b < a))
      c = true;
   else
      c = false;

   if( !(a == b)&& (b < a))
      c = true;
   else
      c = false;
}

结果

c = true
c = true
c = true

位运算符

假设变量A为60，变量B为13，则：

例如

void setup () {
   int a = 10,b = 20
   int c = 0;
   c = a & b ;
   c = a | b ;
   c = a ^ b ;
   c = a ~ b ;
   c = a << b ;
   c = a >> b ; 
}

结果

c = 12
c = 61
c = 49
c = -60
c = 240
c = 15

复合运算符
假设变量A为10，变量B为20，则：

例子

void setup () {
   int a = 10,b = 20
   int c = 0;

   a++;
   a--;
   b += a;
   b -= a;
   b *= a;
   b /= a;
   a %= b;
   a |= b;
   a &= b;
}

结果

a = 11
a = 9
b = 30
b = 10
b = 200
b = 2
a = 0
a = 61
a = 12