Pointers, Classes, and Sorted Arrays Project

[mbraha123]

I'm building a program that is supposed to take an array, initially empty, and insert user input numbers. Also, after the user inputs a negative number, the numbers that follow are to be removed. The catch is that the array must be sorted in ascending order the whole time and print the array after every insertion or removal. As of now, the program just outputs -33686019 0 alternatively. I don't know why the zero is even there because nowhere do I set any variable to that value. I'm also unsure if my overloaded operators are correct as I do not get that concept. An explanation of this would be very helpful. What's commented out is my first attempt at creating the insert/remove function, respectively.
With the user input as:1 3 2 7 5 9 7 -1 5 7 3 -1
The output should be:

1
1 3
1 2 3
1 2 3 7
1 2 3 5 7
1 2 3 5 7 9
1 2 3 5 7 7 9
1 2 3 5 6 7 7 9
1 2 3 6 7 7 9
1 2 3 6 7 9
1 2 6 7 9
2 6 7 9

#include <iomanip>
#include <iostream>
#include <cmath>
#include <cstdlib>

using namespace std;

class SortedArray{
private:
	int len;
	int *n;
public:
	SortedArray();
	void insert(int);
	void remove(int);
	void print();
	void sort(int*, int);
	SortedArray operator +(int );
	SortedArray operator -(int);
};

SortedArray::SortedArray(void){
   n=new int[1];
   n[0]='\0';
   len=1;
}

void SortedArray::sort(int *a, int b){
	bool sorted;
	int i=0;
	int temp;
	do{
		sorted=true;
		for(i=0; i<b; i++){
			if(a[i]>a[i+1]){
				temp=a[i];
				a[i]=a[i+1];
				a[i+1]=temp;
				sorted=false;
			}
		}
	}while(!sorted);
}

void SortedArray::insert(int num){
	len++;
	int *tmp=n;
	n=new int[len];
	for(int i=0; i<len-1; i++) n[i]=tmp[i];
	n[len-2]=num;
	n[len-1]='\0';
	sort(n, len);
}

	/*int l=len+1;
	int *newArray=new int[l];
	for(int i=0; i<l-1; i++) {
		newArray[i]=n[i];
	}
	newArray[l-1]='\0';
	newArray[l-2]=num;
	delete []n;
	int *n2=new int[l];
	for(int i=0; i<=l-1; i++) {
		n2[i]=newArray[i];
	}
	n=n2;
	delete []newArray;
	sort(n, l);
	len++;*/

void SortedArray::remove(int num) {
	len--;
	int *tmp=n;
	n=new int[len];
	for (int i=0; i<len-1; i++){
		if(tmp[i]==num) tmp[i]=99;
	}
	for(int k=0; k<len; k++) n[k]=tmp[k];
	sort(n, len);
	n[len-1]='\0';
	
}

	
	/*int *newArray;
	int l=len-1;
	for(int i=0; i<len; i++) {
		if(n[i]=num) {
			n[i]=50;
			int *newArray=new int[l];
			for(int j=0; j<len-1; j++) {
				newArray[j]=n[j];
			}
		sort(newArray, l);
		newArray[l-1]='\0';
		delete []n;
		int *n2=new int[l];
		for (int k=0; k<l; k++) {
			n2[k]=newArray[k];
		}
		n=n2;
		delete []newArray;
		len--;
		}
	}*/


void SortedArray::print(){
	for (int i=0; i<len; i++) {
		cout << n[i] <<" ";
	}
	cout<<endl;
}

SortedArray SortedArray::operator +(int num) {
	SortedArray z;
	z.insert(num);
	return z;
}

SortedArray SortedArray::operator -(int num) {
   SortedArray y;
   y.remove(num);
   return y;	
}


int main(){
	SortedArray x;
	int inp;
	cin >> inp;
	do{
		x.insert(inp);
		x.print();
		cin >> inp;
	}while(inp >= 0);
	x+6;
	x.print();
	do{
		cin >> inp;
		x.remove(inp);
		x.print();
	}while(inp>=0);
	x-1;
	x.print();

	system ("PAUSE");
	return 0;
}

[mbraha123]

Please someone help!!!