Segmentation Fault In Probability Calculator

Question

I'm compiling this on linux. It will compile and run, but when I enter values for n and p, this is what my terminal looks like:

7 1.0 Segmentation fault (core dumped)

In this case, 7 is the input for n, and 1.0 is the input for p. I've tried this with different values. The idea is to use Dynamic Programming to fill in a 2D array of probabilities through recursion. Let me know if you need more info, but this is the entirety of the code.

#include <iostream>
using namespace std;

int main(int argc, char *argv[])
{

  int n;
  double p;

  cin >> n;
  cin >> p;

  cout << n;
  cout << p;

  cout << "Initializing array.";
  double** probability = new double*[n];
  for(int i = 0; i < n; ++i)
  {
     probability[i] = new double[n];
  }

  //cout << "Beginning filling i loop.";
  for(int i = 0; i < n; i++)
  {
     probability[i][0] = 0;
  }
  //cout << "Beginning filling j loop.";

  for(int j = 0; j < n; j++)
  {
     probability[0][j] = 1;
  }

  //cout << "Beginning filling nested loop.";
  for(int i = 1; i< n; i++)
  {
     for(int j = 1; j< n; j++)
     {
        probability[i][j] = (p * probability[i-1][j]) + ((1-p) * probability[i][j-1]);
     }
  }

  cout << "Probability: ";
  cout << probability[n][n];

  //cleanup
  for(int i = 0; i < n; ++i)
  {
    delete probability[i] ;
  }
  delete probability;

  return 0;
}

Answer 1

cout << probability[n][n];

probability[][] is an n by n array. The last element is probability[n-1][n-1] , so you are running off the end of the array and invoking undefined behavior.