我没有得到任何错误或类似的东西，但问题是无论我做什么，我都无法摆脱那些内存泄漏。我找到的唯一解决方案是帮助我在每个方法之后添加delete[] vector1，但我不允许修改代码的那部分。
在代码中，您可以看到注释以及我可以添加新指令的区域。我的问题有解决办法吗？
这是代码：
#include<iostream>
using namespace std;
/*YOU CAN'T ADD NEW METHODS*/
/*YOU CAN ONLY MODIFY THE BODY OF THE METHODS*/
//read array from the console - number of elements and the elements
int * readVectorVersion1(int * noElements) {
int *vector1;
vector1 = new int[*noElements + 1];
for (int i = 0; i < *noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector1[i];
}
return vector1;
}
//read array from the console - number of elements and the elements
void readVectorVersion2(int ** vector, int* noElements) {
*vector = new int[*noElements + 1];
for (int i = 0; i < *noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> (*vector)[i];
}
}
//read array from the console - number of elements and the elements
void readVectorVersion3(int *& vector, int& noElements) {
vector = new int[noElements + 1];
for (int i = 0; i < noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector[i];
}
}
//read array from the console - number of elements and the elements
int * readVectorVersion4(int& noElements) {
int *vector1;
vector1 = new int[noElements + 1];
for (int i = 0; i < noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector1[i];
}
return vector1;
}
//read static array from the console - number of elements and the elements
void readStaticVector(int vector[], int * noElements) {
for (int i = 0; i < *noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector[i];
}
}
//print the elements of the array
void afisareVector(int* vector, int noElements) {
cout << endl << "Vector:" << endl;
for (int i = 0; i < noElements; i++)
cout << vector[i] << " ";
}
//read a name from the console
char* citesteNume() {
char temp[200];
char * nume;
cout << endl << "Your name:";
cin >> temp;
nume = new char[strlen(temp) + 1];
strcpy(nume, temp);
return nume;
}
//read a name from the console
void citesteNume(char* nume) {
cout << endl << "Your name:";
cin >> nume;
}
//METHODS THAT ADDS AN ELEMENT (THAT IS GIVEN) TO AN EXISTING ARRAY
//FIRST
void adaugaElementNou(int** vector, int* noElemente, int elementNou) {
(*vector) = new int[*noElemente + 2];
for (int i = 0; i < *noElemente; i++)
(*vector)[i] = i;
(*vector)[*noElemente] = elementNou;
}
//SECOND
int * adaugaElementNou(int& noElemente, int elementNou) {
int *vector;
vector = new int[noElemente + 2];
for (int i = 0; i < noElemente; i++)
vector[i] = i;
vector[noElemente] = elementNou;
return vector;
}
//THIRD
int * adaugaElementNou(int* noElemente, int elementNou) {
int *vector;
vector = new int[(*noElemente) + 2];
for (int i = 0; i < *noElemente; i++)
vector[i] = i;
vector[*noElemente] = elementNou;
return vector;
}
//THE PROGRAM MUST RUN AND NOT GENERATE ANY ERRORS OR MEMORY-LEAKS
void main() {
//YOU CAN'T ADD NEW VARIABLES
int * vector1;
int vector2[50];
int nrElementeVector1=3;
int nrElementeVector2=3;
//YOU CAN ADD NEW INSTRUCTIONS
// ...
vector1 = new int[nrElementeVector1 + 1];
for (int i = 0; i < nrElementeVector1; i++)
vector1[i] = i;
for (int i = 0; i < nrElementeVector2; i++)
vector2[i] = i;
//YOU CAN'T MODIFY THE FOLLOWING CODE
afisareVector(vector1, nrElementeVector1);
afisareVector(vector2, nrElementeVector2);
//delete[]vector1; /*This instruction is added by me but i`m not allowed to modify this area of the code*/
vector1 = readVectorVersion1(&nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
//delete[]vector1;
readVectorVersion2(&vector1, &nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
//delete[]vector1;
readVectorVersion3(vector1, nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
//delete[]vector1;
vector1 = readVectorVersion4(nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
//delete[]vector1;
readStaticVector(vector2, &nrElementeVector2);
afisareVector(vector2, nrElementeVector2);
char* string1;
char string2[50];
string1 = citesteNume();
cout << endl << "Hello " << string1;
//delete[]string1; /*THIS IS NOT ALLOWED HERE*/
citesteNume(string2);
cout << endl << "Hello " << string2;
vector1 = adaugaElementNou(nrElementeVector1, 99);
afisareVector(vector1, nrElementeVector1+1);
//delete[]vector1;
adaugaElementNou(&vector1, &nrElementeVector1, 55);
afisareVector(vector1, nrElementeVector1+1);
//delete[]vector1;
vector1 = adaugaElementNou(&nrElementeVector1, 77);
afisareVector(vector1, nrElementeVector1+1);
//delete[]vector1;
//YOU CAN ADD NEW INSTRUCTIONS HERE
// ...
delete[] vector1; //I`ve tried to use delete here because I didn`t knew what else i should do, but I know that it makes no sense(and it`s not working);
delete[] string1;
//THE FOLLOWING CODE CHECKS IF THERE ARE ANY MEMORYLEAKS
_CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_FILE);
_CrtSetReportFile(_CRT_WARN, _CRTDBG_FILE_STDOUT);
_CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_FILE);
_CrtSetReportFile(_CRT_ERROR, _CRTDBG_FILE_STDOUT);
_CrtSetReportMode(_CRT_ASSERT, _CRTDBG_MODE_FILE);
_CrtSetReportFile(_CRT_ASSERT, _CRTDBG_FILE_STDOUT);
_CrtDumpMemoryLeaks();
//YOU CAN'T MODIFY THE FOLLOWING CODE
vector1 = NULL;
string1 = NULL;
cout << endl << "In this moment there are no memory-leaks!";
}
答案 0 :(得分：0)
我说这个任务是不可能完成的。这条线
vector1 = readVectorVersion1(&nrElementeVector1);
。此时创建不可恢复的泄漏。以下
也是如此readVectorVersion2(&vector1, &nrElementeVector1);
答案 1 :(得分：0)
vector1指针会覆盖在您可能无法修改的代码中，因此很明显它可能不是唯一指向动态分配内存的指针，否则它会泄漏并且您无法阻止它，在你的任务限制范围内。
因此，让我们探讨使用静态对象来保存指针的可能性。为简单起见，我将使用std::vector，但如果您愿意，可以使用静态指针指向动态内存。在这种情况下，您需要手动管理内存。
int * readVectorVersion1(int * noElements) {
static std::vector<int> vector1;
vector1.resize(*noElements);
// initialize the way you want to
return vector1.data();
// return &vector1[0]; // use this if you use older version of c++ than c++11
}
你去吧。当破坏静态对象时，将释放内存。这当然限制了你可以用这个功能做什么。您不能再分配两个单独的数组，因为后续调用将使用相同的向量。但是这个任务并不需要，所以我想这就是你的导师所要求的。
答案 2 :(得分：0)
对于string1来说很简单，你可以：
delete[] string1;
这就是我认为你应该处理的vector1：
void afisareVector(int* vector, int noElements) {
cout << endl << "Vector:" << endl;
for (int i = 0; i < noElements; i++)
cout << vector[i] << " ";
// A very dirty hack, PLEASE **NEVER** USE IT.
static int callIndex = 0;
if(callIndex != 1 && callIndex != 6)
delete[] vector;
++callIndex;
}
valgrind摘要：
==20937== HEAP SUMMARY:
==20937== in use at exit: 0 bytes in 0 blocks
==20937== total heap usage: 9 allocs, 9 frees, 144 bytes allocated
==20937==
==20937== All heap blocks were freed -- no leaks are possible
==20937==
==20937== For counts of detected and suppressed errors, rerun with: -v
==20937== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
编辑：我改变了主意。上面的例子是你可以做的，这是你应该做的：
注意＃1：这个黑客对我来说更脏了。
注意＃2：为了编译它，我必须删除所有特定于Microsoft的东西并使用valgrind执行泄漏检查。
#include<iostream>
#include<cstring>
using namespace std;
/*YOU CAN'T ADD NEW METHODS*/
/*YOU CAN ONLY MODIFY THE BODY OF THE METHODS*/
//read array from the console - number of elements and the elements
int * readVectorVersion1(int * noElements) {
static int vector1[50];
for (int i = 0; i < *noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector1[i];
}
return vector1;
}
//read array from the console - number of elements and the elements
void readVectorVersion2(int ** vector1, int* noElements) {
static int vector [50];
for (int i = 0; i < *noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector[i];
}
*vector1 = vector;
}
//read array from the console - number of elements and the elements
void readVectorVersion3(int *& vector1, int& noElements) {
static int vector [50];
for (int i = 0; i < noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector[i];
}
vector1 = vector;
}
//read array from the console - number of elements and the elements
int * readVectorVersion4(int& noElements) {
static int vector1 [50];
for (int i = 0; i < noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector1[i];
}
return vector1;
}
//read static array from the console - number of elements and the elements
void readStaticVector(int vector[], int * noElements) {
for (int i = 0; i < *noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector[i];
}
}
//print the elements of the array
void afisareVector(int* vector, int noElements) {
cout << endl << "Vector:" << endl;
for (int i = 0; i < noElements; i++)
cout << vector[i] << " ";
}
//read a name from the console
char* citesteNume() {
char temp[200];
char * nume;
cout << endl << "Your name:";
cin >> temp;
nume = new char[strlen(temp) + 1];
strcpy(nume, temp);
return nume;
}
//read a name from the console
void citesteNume(char* nume) {
cout << endl << "Your name:";
cin >> nume;
}
//METHODS THAT ADDS AN ELEMENT (THAT IS GIVEN) TO AN EXISTING ARRAY
//FIRST
void adaugaElementNou(int** vector, int* noElemente, int elementNou) {
static int vector1 [50];
for (int i = 0; i < *noElemente; i++)
vector1[i] = i;
vector1[*noElemente] = elementNou;
*vector = vector1;
}
//SECOND
int * adaugaElementNou(int& noElemente, int elementNou) {
static int vector [50];
for (int i = 0; i < noElemente; i++)
vector[i] = i;
vector[noElemente] = elementNou;
return vector;
}
//THIRD
int * adaugaElementNou(int* noElemente, int elementNou) {
static int vector [50];
for (int i = 0; i < *noElemente; i++)
vector[i] = i;
vector[*noElemente] = elementNou;
return vector;
}
//THE PROGRAM MUST RUN AND NOT GENERATE ANY ERRORS OR MEMORY-LEAKS
int main() {
//YOU CAN'T ADD NEW VARIABLES
int * vector1;
int vector2[50];
int nrElementeVector1=3;
int nrElementeVector2=3;
//YOU CAN ADD NEW INSTRUCTIONS
for (int i = 0; i < nrElementeVector2; i++)
vector2[i] = i;
vector1 = vector2;
//YOU CAN'T MODIFY THE FOLLOWING CODE
afisareVector(vector1, nrElementeVector1);
afisareVector(vector2, nrElementeVector2);
vector1 = readVectorVersion1(&nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
readVectorVersion2(&vector1, &nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
readVectorVersion3(vector1, nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
vector1 = readVectorVersion4(nrElementeVector1);
afisareVector(vector1, nrElementeVector1);
readStaticVector(vector2, &nrElementeVector2);
afisareVector(vector2, nrElementeVector2);
char* string1;
char string2[50];
string1 = citesteNume();
cout << endl << "Hello " << string1;
citesteNume(string2);
cout << endl << "Hello " << string2;
vector1 = adaugaElementNou(nrElementeVector1, 99);
afisareVector(vector1, nrElementeVector1+1);
adaugaElementNou(&vector1, &nrElementeVector1, 55);
afisareVector(vector1, nrElementeVector1+1);
vector1 = adaugaElementNou(&nrElementeVector1, 77);
afisareVector(vector1, nrElementeVector1+1);
//YOU CAN ADD NEW INSTRUCTIONS HERE
// ...
delete[] string1;
//YOU CAN'T MODIFY THE FOLLOWING CODE
vector1 = NULL;
string1 = NULL;
}
valgrind输出：
==21224== HEAP SUMMARY:
==21224== in use at exit: 0 bytes in 0 blocks
==21224== total heap usage: 1 allocs, 1 frees, 2 bytes allocated
==21224==
==21224== All heap blocks were freed -- no leaks are possible
==21224==
==21224== For counts of detected and suppressed errors, rerun with: -v
==21224== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
编辑：我想出了第三个（甚至更脏）的解决方案，但我已经厌倦了所有这些黑客写一个完整版本。这是一个例子：
int * readVectorVersion1(int * noElements) {
static int *vector1 = NULL;
delete[] vector1;
if (noElements < 0)
return NULL;
vector1 = new int[*noElements + 1];
for (int i = 0; i < *noElements; i++)
{
cout << endl << "Vector1[" << i + 1 << "]=";
cin >> vector1[i];
}
return vector1;
}
// ...
int main() {
// ...
// Just before _CrtSetReportMode
nrElementeVector1 = -1;
readVectorVersion1(*nrElementeVector1);
// ..
}