Question

由于此输出，我的程序停止工作。我该如何解除分配？我尝试了我的代码，但没有帮助。完整代码可以在这里找到：full code

for ( i = 0 ; i < n ; i++ ) {
    if (
       !( (x[i] >= 0) && (x[i] <= a) &
          (y[i] >= 0) && (y[i] <= b)
        )
    ) {
        cout << x[i] << ' ' << y[i] << ' ' << s[i] << ' ' << "SPADOL" << endl;
    } else {
       cout << x[i] << ' ' << y[i] << ' ' << s[i] << endl;
    } // ALLOCATION IS DONE AT THIS POINT

    delete [] x;  
    delete [] y;  
    delete [] s;
}

当我运行此代码时，我开始输入x和y，然后在输入y值之后，程序停止工作。当我只输入一行时，程序执行完美，但当我想输入多行时出现问题，..程序在打印出第一个输出后立即崩溃。我的完整代码与矢量：

#include <iostream>
#include <string>
#include <vector>
#include <stdlib.h>
#include <string>

using namespace std;
// vector<string> inputs;
int n; // pocet uloh
int a; // rozmer obdlznika a
int b; // rozmer obdlznika b
vector<int> x;
vector<int> y;
vector<string> s;
int i;
int d;

static const char alpha[] = {'D', 'L', 'P'};
char genRandom()
{
    return alpha[rand() % strlen(alpha)];
}
// end of generator


int main() {

    cin >> n;

    while(!((n >= 1)&&(n <=15000)))
    {
           cout << "max 15000" << flush;
           cin >> n;
           }


    cin >> a >> b;

    while(!((a >= 1)&&(a <=100) & (b >= 1)&&(b <= 100)&&(a!=b)))
    {
           cout << "chyba max 100 alebo a!=b" << endl;
           cin >> a >> b;
           }


        for (i = 0; i < n; i++)
               {    
                    cout << "Uloha " << i+1 << ":" << endl;

                    cin >> x[i];
                    cin >> y[i];
                    cin >> s[i];

                    while(!((x[i]>=0)&&(x[i]<=a))) {
                    cout << "Try Again x: " << flush;
                    cin >> x[i];}
                    while(!((y[i]>=0)&&(y[i]<=b))) {
                    cout << "Try Again y: " << flush;
                    cin >> y[i];}


                    if (s[i] == "S"){
                          y[i] = (y[i]+1);
                          }else if (s[i] == "J"){
                                y[i] = (y[i]-1);
                                }else if (s[i] == "V"){
                                      x[i] = (x[i]+1);
                                      }else if (s[i] == "Z"){
                                            x[i] = (x[i]-1);
                                            }
                    cin >> d;
                    while(!((d>=1)&& (d<=200))) {
                    cout << "Try Again d: " << flush;
                    cin >> d;}


                   for (int counter=0; counter<d; counter++)
                   {
                   cout << genRandom();
                   }
                   cout << endl;

          }    // koniec for

          for ( i = 0 ; i < n ; i++ )
                                     {
                                         if(!(((x[i]>=0)&&(x[i]<=a)) | ((y[i]>=0)&&(y[i]<=b)))){
                                                  cout << x[i] << ' ' << y[i] << ' ' << s[i] << ' ' << "SPADOL" << endl;
                                                  }else{
                                                  cout << x[i] << ' ' << y[i] << ' ' << s[i] << endl;

                                                  }

                                     } 




system("pause");

}

Answer 1

假设要通过x和y动态分配数组s，new[]和n > 1，您的循环将解除分配x，第一次y，s，然后尝试在下一次迭代中阅读x[i]。

你应该将delete[]移到循环之外，或者甚至更好，你应该使用自动清理自己的容器，比如std::vector：

std::vector<int> x;
std::vector<int> y;
std::vector<int> s;

for (i = 0 ; i < n ; i++) {
    if (
       !( (x[i] >= 0) && (x[i] <= a) &
          (y[i] >= 0) && (y[i] <= b)
        )
    ) {
        cout << x[i] << ' ' << y[i] << ' ' << s[i] << ' ' << "SPADOL" << endl;
    } else {
       cout << x[i] << ' ' << y[i] << ' ' << s[i] << endl;
    }
}

Answer 2

如果您没有使用关键字“new”进行分配，则无需调用delete。如果在堆上分配，则只需要解除分配。使用标准的lib类，让它们在内部对堆执行new / delete。

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