C++ Sudoku using Backtracking/Recursion

[jessemcready]

My teacher wants us to make an NxN sudoku puzzle and solve it using random numbers from 1 to N. There can be no repeats in rows or column, everything else is fine. Recursion or backtracking has to be used. Here's what I have so far.

#include<iostream>
#include<time.h>
#include<cstdlib>
#include<cstdio>
using namespace std;


void fill_puzzle(int size);
void delete_puzzle(int **array, int size);
bool check_correct(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 size){
	int **array;
	array=new int*[size];
	for (int i=0; i<size; i++){
		array[i]=new int [size];
	}
	srand((unsigned int)time(NULL));
	if(check_correct(array,size)==false)
		for(int i=0; i<size; i++){
			for (int j=0; j<size; j++){
			 	array[i][j]=(rand() % size);
				fill_puzzle(size-1);
		}
	}
	else {
		for (int i=0;i<size;i++)
			for(int j=0;j<size;j++)
				cout << array[i][j];
	}
	delete_puzzle(array,size);					
}

void delete_puzzle(int **array, int size){
	for (int i=0; i<size; i++){
		delete [] array[i];
	}
	delete []array;
}

int main(){
	int  size=0;
	cout << "Hello, what size puzzle would you like to create? Please type a number. Example: 3 would make a 3x3 sudoku puzzle."<<endl;
	cin >> size;
	if (size > 0){
		fill_puzzle(size);
			
	}
	else {
		cout << "Invalid size. Must be greater than 0." <<endl;
		exit (0);
	}
	
	return 0;
}

When I compile, I get no output except the bit where it asks the user for the size. Any help would be appreciated, thank you.

[LB]

Do you have to use backtracking/recursion?

[jessemcready]

Yeah, it's what we are learning in class, so he wants us to know how to implement it.