- int main()
- {
- int a = (1,2,3);
- int b = (++a,++a,++a);
- int c= (b++,b++,b++);
- printf("%d %d %d",a,b,c);
- }
解决方法
用于所有三个声明
- int a = (1,3);
- int b = (++a,++a);
- int c = (b++,b++);
它是comma operator.它计算第一个操作数1并丢弃它,然后计算第二个操作数并返回其值.因此,
- int a = ((1,2),3); // a is initialized with 3.
- int b = ((++a,++a),++a); // b is initialized with 4+1+1 = 6.
- // a is 6 by the end of the statement
- int c = ((b++,b++),b++); // c is initialized with 6+1+1 = 8
- // b is 9 by the end of the statement.
1在逗号运算符的情况下,从左到右保证评估顺序.
