当我们使用do-while循环并在用逗号分隔的while循环中写入常量时，无法预测输出

Question

int i=40;         //defined    
int main()
{
    do
    {
        printf("%d",i++);
    }while(5,4,3,2,1,0);  //what does this do ?

    return 0;
}

**O/P=40**

I am unable to figure out what the while loop does in the above code.....

I know that do while loop execute atleast once.As the O/P=40 condition of while loop evaluates to false but iam unable to figure out how?

Answer 1

The result of expression

5,4,3,2,1,0

is 0 . So do - while is executed exactly one time.

See Comma operator .