issues with Storing to array [closed] - c++

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I was testing one of my classes, but for some reason I can't seem to cast an intiger from a 2d array to double. Here is my (very simplified) code:
In main.cpp
#include<iostream>
#include<conio.h>
#include<string>
#include "trajectories.h"
int main()
{
std::string response;
int numOfCoords;
int speed;
int ** coords;
std::cout<<"enter the number of coordinates: ";
std::cin>>numOfCoords;
std::cout<<"enter speed: ";
std::cin>>speed;
coords=new int *[numOfCoords];
for (int i=0; i<numOfCoords; i++)
coords[i] = new int[2];
for(int i=0; i<numOfCoords*2; i++)
{
if(i%2==0)
std::cout<<"enter point "<<i/2<<".x : ";
else
std::cout<<"enter point "<<i/2<<".y : ";
std::cin>>coords[i/2][i%2];
}
NPCTrajectory traj(numOfCoords, speed);
traj.AddCoordinates(coords);
std::cout<<coords[0][0]<<", "<<coords[0][1]<<std::endl;
getch();
double currentCoords[2];
currentCoords[0]=double(coords[0][0]);
currentCoords[1]=double(coords[0][1]);
for(;;)
{
traj.HandleEvents(currentCoords);
std::cout<<"current coordinates : ("<<currentCoords[0]<<", "<<currentCoords[1]<<")"<<std::endl;
std::cout<<"do you wish to continue? ";
getch();
}
}
Trajectories.h contains class declaration only, so I believe it is irrelevant. Here is my trajectories.cpp
#include "trajectories.h"
int FPSCap=5;
NPCTrajectory::NPCTrajectory(int npoints, int newSpeed)
{
numOfPoints=npoints;
this->speed=newSpeed;
points = new int * [npoints];
for (int i=0; i<npoints; i++)
points[npoints] = new int[2];
state = 0;
maxOffset=speed/FPSCap;
}
void NPCTrajectory::AddCoordinates(int ** coordinates)
{
for(int i=0;i<this->numOfPoints; i++)
{
points[i][0]=coordinates[i][0];
points[i][1]=coordinates[i][1];
}
}
void NPCTrajectory::HandleEvents(double (&currentCoordinates)[2])
{
if(state+1==numOfPoints) return;
if(Distance(currentCoordinates[0], currentCoordinates[1], (double)points[state+1][0], (double)points[state+1][1])<maxOffset) state++;
double ratio = maxOffset/Distance(currentCoordinates[0], currentCoordinates[1], (double)points[state+1][0], (double)points[state+1][1]);
currentCoordinates[0]+=(points[state+1][0]-currentCoordinates[0])*ratio;
currentCoordinates[1]+=(points[state+1][1]-currentCoordinates[1])*ratio;
}
Please note that removing command traj.AddCoordinates(coords) will make the problem disappear. Am I passing the array correctly to the function?

Answer 1

The problem is in your constructor NPCTrajectory. Replace npoints with loop variable i. The following code:
for (int i=0; i<npoints; i++)
points[npoints] = new int[2];
should be like:
for (int i=0; i<npoints; i++)
points[i] = new int[2];
Because of this incorrect allocation, you are getting error (segmentation fault) in AddCoordinates function when you try to access points[i][0] with i=0 (assuming you are giving npoints>0 in NPCTrajectory).