下表列出了所有C语言支持的算术运算符。假设变量A=10和变量B=20则：
| 运算符 | 描述 | 示例 |
|---|---|---|
| + | 两个操作数相加 | A + B = 30 |
| - | 第一操作数减去第二个操作数 | A - B = -10 |
| * | 两个操作数相乘 | A * B = 200 |
| / | 分子除以分母 | B / A = 2 |
| % | 模运算和整数除法后的余数 | B % A = 0 |
| ++ | 递增操作者增加一个整数值 | A++ = 11 |
| -- | 递减操作减少一个整数值 | A-- = 9 |
试试下面的例子就明白了所有的C编程语言提供的算术运算符：
#include <stdio.h>
main()
{
int a = 21;
int b = 10;
int c ;
c = a + b;
printf("Line 1 - Value of c is %d
", c );
c = a - b;
printf("Line 2 - Value of c is %d
", c );
c = a * b;
printf("Line 3 - Value of c is %d
", c );
c = a / b;
printf("Line 4 - Value of c is %d
", c );
c = a % b;
printf("Line 5 - Value of c is %d
", c );
c = a++;
printf("Line 6 - Value of c is %d
", c );
c = a--;
printf("Line 7 - Value of c is %d
", c );
}
当编译和执行上面的程序，它会产生以下结果：
Line 1 - Value of c is 31 Line 2 - Value of c is 11 Line 3 - Value of c is 210 Line 4 - Value of c is 2 Line 5 - Value of c is 1 Line 6 - Value of c is 21 Line 7 - Value of c is 22
