C++ Assertion Failed on vector at runtime Expression: vector subscript out of range
im gettin this really annoying error message. I know Im only new to this but it seems the type of thing I could figure out. Can anyone show me where im going wrong please?
The message at run time is: Debug Assertion Failed! Program: .... File: c:\program files\microsoft visual studio 10.0\vc\include\vector Line: 932 Expression: Vector subscript out of range
and the code is
#include "VectorIntStorage.h"
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;
void VectorIntStorage::Read(istream& r)
{
char c[13];
r >> c;
r >> NumberOfInts; //gets number of ints for vector
//numberVector = new std::vector<int> numberVector;
for(int i = 0; i < NumberOfInts; i++)
{
r >&开发者_开发技巧gt; numberVector[i];
cout << numberVector[i] << endl;
if(_sortRead) //true
{
for(int k = 0; k < i; k++)
{
if(numberVector[i] < numberVector[k])
{
int temp = numberVector[k];
numberVector[k] = numberVector[i];
numberVector[i] = temp;
}
}
}
}
}
void VectorIntStorage::Write(ostream& w)
{
for(int i = 0; i < NumberOfInts; i++)
{
w << numberVector[i] << endl;
cout << numberVector[i] << endl;
}
}
void VectorIntStorage::sortStd()
{
sort(numberVector.begin(), numberVector.end());
}
void VectorIntStorage::sortOwn()
{
quickSort(0, NumberOfInts - 1);
}
void VectorIntStorage::setReadSort(bool sort)
{
_sortRead = sort;
}
void VectorIntStorage::quickSort(int left, int right)
{
int i = left, j = right;
int tmp;
int pivot = numberVector[(left + right) / 2];
while (i <= j)
{
while (numberVector[i] < pivot)
i++;
while (numberVector[j] > pivot)
j--;
if (i <= j)
{
tmp = numberVector[i];
numberVector[i] = numberVector[j];
numberVector[j] = tmp;
i++;
j--;
}
}
if (left < j)
{
quickSort(left, j);
}
if (i < right)
{
quickSort(i, right);
}
}
VectorIntStorage::VectorIntStorage(const VectorIntStorage& copying)
{
//int *duplicate = new int[(copying.NumberOfInts)];
//vector<int> *duplicate = new vector<int>;
//std::copy(numberVector.begin(), numberVector.end(), duplicate);
//numberVector = duplicate;
//NumberOfInts = copying.NumberOfInts;
}
VectorIntStorage::VectorIntStorage(void)
{
}
VectorIntStorage::~VectorIntStorage(void)
{
}
We don't have enough information to say for sure, but I suspect the failing line is r >> numberVector[i]
. I suppose you meant to say int j; r >> j; numberVector.push_back(j);
The problem is precisely what the error message says: your vector subscript (i
) is out of range. Specifically, you never increase the size of your vector, so it is always of size 0. Thus, any use of operator[]
is going to reference an out-of-range element.
You can't just use numberVector[i]
without calling numberVector.resize()
first.
vector<int> vec;
vec[1] = 0; // fails - vec is empty so [1] is out of range
vec.resize(100);
vec[1] = 5; // ok, you can access vec[0] .. vec[99] now
vec.push_back(11); // Now the size is 101 elements, you can access vec[0] .. vec[100]
r >> NumberOfInts; //gets number of ints for vector
From the above comment, it seems you need a vector of size NumberOfInts
. But leaving the line as commented -
//numberVector = new std::vector<int> numberVector;
You are declaring the vector as -
std::vector<int> numberVector; // The size of the vector is 0
To perform the operation of []
on numberVector
, it's size should be mentioned and should be in the valid range while declaration. Since it not mentioned while declaration, you need to do a push_back
operation to dynamically increase the size of the vector.
for(int i = 0; i < NumberOfInts; i++)
{
r >> numberVector[i]; // Size isnot initially mentioned while declaration
// of the vector to do an `[]` operation
cout << numberVector[i] << endl;
// ....
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