Using Recursion/Backtracking to create and solve a sudoku puzzle - c++

Question

For my computer class, my teacher wants us to use recursion or backtracking to create and solve an nXn size sudoku puzzle. The puzzle has to be dynamically allocated and the only rules for the puzzle is that there can be no repetition in any rows or columns. Diagonals and smaller sub-squares can have repeats. Here is what I have written so far.
#include<iostream>
#include<time.h>
#include<stdlib.h>
#include<stdio.h>
using namespace std;
void fill_puzzle(int **array, int size);
void delete_puzzle(int array, int size);
bool check_filled(int **array, int size);
bool check_correct(int **array, int size){
int temp=0;
for(int i=0; i<size; i++){
for (int j=0; j<size; j++){
for (int k=0;k<size;k++){
if (array[i][k]==array[i][j])
return false;
else
return true;
}
}
}
}
void fill_puzzle(int **array, int size){
srand(time(NULL));
int random_number;
random_number=(rand()%size);
while(check_correct(array,size)==false)
for(int i=0; i<size; i++){
for (int j=0; j<size; j++){
array[i][j]=random_number;
if (check_correct(array, size) ==false)
fill_puzzle(array, size);
else
cout << array[i][j];
}
}
}
void delete_puzzle(int **array, int size){
for (int i=0; i<size; i++){
delete [] array[i];
}
delete []array;
}
int main(){
int size=0;
int **array;
cout << "Hello, what size puzzle would you like to create? Please type 1 number. Example: 3 would make a 3x3 sudoku puzzle."<<endl;
cin >> size;
if (size <= 0){
cout << "The size you have chosen will not work, please choose a number greater than 0." << endl;
cin >> size;
for (int i=0; i<size; i++){
array=new int*[size];
array[size]=new int [size];
}
}
else {
for (int i=0; i<size; i++){
array=new int*[size];
array[size]=new int [size];
}
fill_puzzle(array,size);
delete_puzzle(array, size);
}
return 0;
}
When I try to compile, I get a segmentation error, and using GDB it says that the error occurs in check_correct in the line with if (array[i][k]==array[i][j]). Thanks in advance.

Answer 1

As I can see so far, the code for allocating memory for the 2D array is not correct and the segmentation fault is caused by accessing illegal memory since you didn't allocate properly.
for (int i=0; i<size; i++){
array=new int*[size]; // move it out of loop
array[size]=new int [size]; //array[size]?!
try this:
array = new int*[size];
for(int i = 0; i < size; ++i)
array[i] = new int[size];
There are others problems(fill_puzzle() stuck in an infinite recursion, it leads your stack grow bigger and bigger, until you get a segmentation fault) in your sudoku solver, use a debugger to solve it.