C语言基础-4、复合赋值和递增递减

一、复合赋值

• total += (sum + 100)/2;
• total = total + (sum + 100)/2;
• total *= sum + 12;
• total = total*(sum + 12);
• 自右向左结合

#include <stdio.h>
int main()
{
    int total = 0;
    int sum = 0;
    total += (sum+100)/2;
    printf("total += (sum+100)/2 = %d\n",total);
    total = 0;
    total = total + (sum+100)/2;
    printf("total = total + (sum+100)/2 = %d\n",total);
    total = 0;
    total *= sum + 12;
    printf("total *= sum + 12 = %d\n",total);
    total = 0;
    total = total*(sum+12);
    printf("total = total*(sum+12) = %d\n",total);
}

二、递增递减运算符
1、前缀后缀

• 前缀

#include <stdio.h>
int main()
{
    int a = 0;
    printf("++a = %d\n",++a);
    return 0;
}

• 后缀

#include <stdio.h>
int main()
{
    int a = 0;
    printf("a++ = %d\n",a++);
    return 0;
}