小编k_z*_*r_k的帖子

我有一些 Java 代码，当我运行函数时，KeyPairGenerator.genKayPair()它可以工作 40 秒或更长时间。如何改变这种状况？如果我跑

openssl req -x509 -nodes -days 365 -newkey rsa:4096 -keyout server.key -out cert.pem 

它的工作 3 秒。慢代码：

KeyPairGenerator gen = KeyPairGenerator.getInstance("RSA");
SecureRandom random = new SecureRandom();
gen.initialize(4096, random);        
keyPair = gen.generateKeyPair();        
PublicKey pubk = keyPair.getPublic();
PrivateKey prvk = keyPair.getPrivate();

我尝试在QT中使用以下头文件:

#include <QUdpSocket>

但我得到错误:

QUdpSocket: No such file or directory

如何忽略所有带名称的文件夹build,bin.我试过这样做

**/bin/
**/build/

但它不起作用.在我看到的git状态

#   new file:   BS/server/build/obj/sender.o
#   new file:   BS/server/build/obj/sendistate.o
#   new file:   BS/server/build/obj/serializedata.o
#   new file:   BS/client/bin/gc.sample.xml
#   new file:   BS/client/bin/mkab.qss
#   new file:   BS/client/bin/mkaberr.qss
#   new file:   BS/client/build/debug/application.qss
#   new file:   BS/client/build/debug/config.xml

我有代码:

#include <iostream>
#include <QThread>
#include <unistd.h>
#include <stdlib.h>
#include <QApplication>


using std::cerr;
using std::endl;

class Thread : public QThread
{
    Q_OBJECT
public:
    Thread();
    ~Thread();
    void setMessage(const QString &_message);
    void stop();
protected:
    void run();
private:
    QString message;
    volatile bool stopped;
};

Thread::Thread()
{
    stopped = false;    
    run();
}

Thread::~Thread()
{

}


void Thread::run()
{
    while(!stopped){
        cerr << qPrintable(message);
        sleep(1);
    }
        stopped = false;
        cerr << endl;
}

void Thread::stop()
{
    stopped = true; 
}

void Thread::setMessage(const QString &_message)
{
    message …

我不明白为什么这段代码有效.

int f(int,int);

int main()
{
    f(12,21);
    return 0;
}

int f(int,int b)
{
    return 0;
}

我如何在函数f(...)中使用第一个arg？

我有以下代码

void foo()
{
    char* pcBlock = new char[1000];
    ...
    delete[] pcBlock;
    ...
    pcBlock = new char[100000];
    ...
    delete[] pcBlock;
}

下面的代码会导致内存泄漏吗？

void foo()
{
    char* pcBlock = new char[1000];
    ...
    pcBlock = new char[100000];
    ...
    delete[] pcBlock;
}

我如何在下一个例子中释放mamory.vt.pop_back()删除vt中的元素,但它不释放内存.删除vt [i]不起作用,它给我分段错误.

#include <vector>
#include <unistd.h>

using namespace std;

const int SIZE = 1000000;

class Test
{
public:
    Test();
    ~Test();    
private:
    int *arr;    
};


int main()
{
    vector<Test *> vt;
    for(int i = 0; i < 100; i++)
        vt.push_back(new Test());
    sleep(10);
    return 0;    
}


Test::Test()
{
    arr = new int[SIZE];
}


Test::~Test()
{
    delete[] arr;
}

我有一些代码.在主要功能中,我在BST中推六个元素.当我看调试器时,我看到变量size = 5,但变量root = null.为什么变量root不会改变.

package Search;

public class BST<Key extends Comparable<Key>, Val> {
private class Node{
    Key key;
    Val val;
    Node left;
    Node right;
    Node prev;
    Node(Key k, Val v){
        key = k;
        val = v;
    }
}
public void push(Key k, Val v){
    push(root,k,v);
}
private void push(Node x, Key k, Val v){
    if(x == null){
        x = new Node(k,v);
        size++;
        return;
    }
    int cmp = x.key.compareTo(k);
    if(cmp > 0)
        push(x.left,k,v);
    else if(cmp < 0)
        push(x.right,k,v);
    else
        x.val …