golang 可以推送和弹出的intlist

Posted 2021-05-24

package main
//file to implement expanding/shrinking intlist with a map
import (
	"fmt"
	"strconv"
)
type IntList struct {
	list map[int]int
	//for keeping track of placement indices and insertion spots
	record map[string]int
}

//creates an IntList and returns it
func createIntList() IntList {
	lst := IntList{list:make(map[int]int), record:make(map[string]int)}
	lst.record["insert"] = 0
	lst.record["last"] = -1
	return lst
}
//appends a new element to the end of the list, and updates the insertion and last element positions
func (il IntList) push(elem int) {
	il.list[il.record["insert"]] = elem
	il.record["insert"] += 1
	il.record["last"] += 1
}
//removes the last element from the intlist and returns it
func (il IntList) pop() int {
	popped, has := il.list[il.record["last"]]
	if has {
		delete(il.list, il.record["last"])
		il.record["last"] -= 1
		il.record["insert"] -= 1
		return popped
	}
	return 0
}
//gets an element in the inlist by the given int key
func (il IntList) get(key int) int {
	got, has := il.list[key]
	if has {
		return got
	}
	return 0
}
//appends a new integer to the left side of the list, by moving all current elements up by one
func (il IntList) pushleft(elem int) {
	for i:=il.record["last"] ;i>=0;i-- {
		il.list[i+1] = il.list[i]
	}
	il.list[0] = elem
	il.record["last"] += 1
	il.record["insert"] += 1
}

//gets a pretty string form of the IntList
func (il IntList) tostring() string {
	lststr := "[ "
	for key := range il.list {
		lststr += strconv.Itoa(il.list[key]) + " "
	}
	lststr += "]"
	return lststr
}


func main() {
  tester := createIntList()
  tester.push(5)
  tester.push(8)
  tester.pushleft(1)
  fmt.Println(tester)
  fmt.Println(tester.tostring())
}

UIViewController 推送和弹出中的问题

【中文标题】UIViewController 推送和弹出中的问题

【英文标题】：Issue in UIViewController push & pop

【发布时间】：2012-06-29 06:01:31

【问题描述】：

我遇到了推送和弹出 UIViewController 的问题。我有两个 UIViewController 说 A 和 B。

我写了一个IBAction，其中我从A 推送到B 喜欢，

B *bView=[[B alloc] initWithNibName:@"B" bundle:nil];
[UIView beginAnimations:@"animation" context:nil];
[UIView setAnimationDuration:0.7];
[self.navigationController pushViewController:bView animated:NO];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.navigationController.view cache:NO];
[UIView commitAnimations];

[bView release]; //Problem is here, If I comment this line, it works fine! else it crashes after my some transitions from A [push] B, B [pop] A.

现在在B 我已经写了一个IBAction 来弹出到A，如下所示

[UIView beginAnimations:@"animation" context:nil];
[UIView setAnimationDuration:0.7];
[UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.navigationController.view cache:NO];
[self.navigationController popViewControllerAnimated:NO];
[UIView commitAnimations];

我也从B 打电话给[super dealloc]

-(void) dealloc

   [super dealloc];

如果我不释放bView，它将不会调用dealloc，并且可能会产生内存问题。

这是因为我应用了动画造成的吗？

我尝试了所有其他方式，例如autorelease、设置bView=nil; 等，但这些对我不起作用！

任何帮助，建议！

【问题讨论】：

【bView release】没有问题；您的 B 类代码中还有其他问题，您可以使用 NSZombie 来跟踪问题的确切位置。或者您可以粘贴 B 类的代码。

NSZombie 已启用，它显示消息message sent to deallocated reference

它会显示一些内存地址，在控制台上你可以使用“po memory-address”查看是哪个实例导致了这个问题。

【参考方案1】：

尝试在动画完成块内释放bView。

您可以使用旧样式+ setAnimationDidStopSelector: 或者如果不需要支持iOS4之前的设备，可以使用动画块animateWithDuration:delay:options:animations:completion: