如何在Haskell中写入双端队列("deque")。newtype Deque a = Deque [a]reverses (x:xs) = (reverses xs) ++ [x]front (Deque []) = error("No front of empty Deque")
back (Deque a) = front(re
嘿,我正在尝试将指针内存分配d =(deque*)malloc(sizeof(deque));移到第一个称为void initDeque()的函数中。我尝试在main中保留声明并在函数中分配内存,但是程序在初始化deque之后就会崩溃,并且不能在其他函数中使用指针。下面是代码: int x; d = (deque*)malloc(sizeof(deque));
initDeque(d);putFront(d,1