算術運算子

1. 算術運算子 (Arithmetic Operators) 說明

   符號	意義	範例	說明
   +	加	a+6	計算 a + 6
   -	減	a-6	計算 a - 6
   *	乘	a*6	計算 a * 6
   /	除	a/6	計算 a / 6
   %	取餘數	a%6	計算 a / 6 的餘數
   ++	遞增	a++, ++a	計算 a 增加 1
   --	遞減	a--, --a	計算 a 減少 1

2. 實例說明：

   [dywang@dyw219 zzz]$ vim op-ari1.c
   [dywang@dyw219 zzz]$ cat op-ari1.c
   #include <stdio.h>
   
   main() {
       int a, c=5;
   	a = c + 3;
       printf("a = c + 3 = %d\n", a);
   	a = c - 3;
       printf("a = c - 3 = %d\n", a);
   	a = c * 3;
       printf("a = c * 3 = %d\n", a);
   	a = c / 3;
       printf("a = c / 3 = %d\n", a);
   	a = c % 3;
       printf("a = c % 3 = %d\n", a);
   	a = c++;
       printf("a = c++ = %d, c = %d\n", a, c);
   	a = ++c;
       printf("a = ++c = %d, c = %d\n", a, c);
   	a = c--;
       printf("a = c-- = %d, c = %d\n", a, c);
   	a = --c;
       printf("a = --c = %d, c = %d\n", a, c);
   }
   

3. 編譯成功

   [dywang@dyw219 zzz]$ gcc -o op-ari1 op-ari1.c
   

4. 執行結果

   [dywang@dyw219 zzz]$ ./op-ari1
   a = c + 3 = 8
   a = c - 3 = 2
   a = c * 3 = 15
   a = c / 3 = 1
   a = c % 3 = 2
   a = c++ = 5, c = 6
   a = ++c = 7, c = 7
   a = c-- = 7, c = 6
   a = --c = 5, c = 5