Need help to explain each step

#include

#include

using namespace std;

class BITSET{

private:

vector<int> bits;

void increaseSet(int n){

long unsigned int s = bits.size(); // modified

bits.resize(s+(32*n));

for(long unsigned int i=s;i

bits[i-1] = 0;

}

}

bool shrink(){

long unsigned int n = bits.size(); // modified

if(n <= 32){

return false;

}

bool shr = true;

for(long unsigned int i = n-32;i

if(bits[i] == 1){

shr = false;

break;

}

}

if(shr){

bits.resize(n-32);

}

return shr;

}

public:

BITSET(){

increaseSet(1);

}

bool Test(long unsigned int bit){ // modified

if(bit < 0 && bit >= bits.size()){

return false;

}

unsigned long n = bit/32;

unsigned long p = bit%32;

unsigned long pos = (n*32) + (31-p);

return bits[pos] == 1;

}

void Set(long unsigned int bit){ // modified

while(bit > bits.size()){

increaseSet(1);

}

unsigned long n = bit/32;

unsigned long p = bit%32;

unsigned long pos = (n*32) + (31-p);

bits[pos] = 1;

}

void Clear(long unsigned int bit){ // modified

if(bit < 0 && bit >= bits.size()){

return;

}

unsigned long n = bit/32;

unsigned long p = bit%32;

unsigned long pos = (n*32) + (31-p);

bits[pos] = 0;

while(shrink());

}

unsigned long GetNumSets(){

return bits.size()/32;

}

void inc(){

increaseSet(1);

}

void print(int n){

if(n < 0 || n > GetNumSets()){

return;

}

for(int i = n*32;i<(n+1)*32;i++){

if(i%32 == 0){

printf(" SET %d: ",i/32);

}

if(i%4 == 0){

printf(" ");

}

printf("%d",bits[i]);

}

}

};

string ToBinary(int val,int space){

BITSET b;

int i = 0;

while(val > 2){

if(val%2 == 0){

b.Clear(i);

}else{

b.Set(i);

}

i++;

val = val/2;

}

if(val == 1){

b.Set(i);

}

if(val == 2){

b.Clear(i);

i++;

b.Set(i);

}

string s = "";

for(int i = 32;i>0;i--){

if(i != 32 && i % space == 0){

s += ' ';

}

if(b.Test(i)){

s += '1';

}else{

s += '0';

}

}

cout<

return s;

}

int main(){

BITSET b;

char command = ' ';

while(command != 'q'){

printf(" CMD >> ");

scanf("%c",&command);

switch(command){

case 't':

{

int n;

scanf("%d",&n);

if(b.Test(n)){

printf(" 1");

}else{

printf(" 0");

}

break;

}

case 's':

{

int n;

scanf("%d",&n);

b.Set(n);

break;

}

case 'g':

{

int n;

scanf("%d",&n);

b.print(n);

break;

}

case 'n':

{

int n = b.GetNumSets();

printf(" Number Of Set : %d",n);

break;

}

case 'q':

{

command = 'q';

break;

}

case 'c':

{

int n;

scanf("%d",&n);

b.Clear(n);

break;

}

default:

printf(" INVALID COMMAND !!! ");

}

char c;

scanf("%c",&c); // modified to handle the buffer, if it should not be done, please comment you will get what you want

}

}