// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
// #pragma GCC optimize("unroll-loops")
		
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<ld> vld;
typedef vector<pair<ll , ll>> vpll;
typedef vector<pair<ld , ld>> vplld;
typedef pair<int,int> pii;
typedef vector<pair<int,int>> vpii;
typedef vector<ll> vl;
typedef pair<ll,ll> pll;
typedef priority_queue<ll> pq;
typedef priority_queue<pair<ll,ll>> pqp;

#define fi first
#define se second
#define pb push_back
#define mp make_pair

#define print(a) for(auto x:a) cout<<x<<" ";cout<<endl;
#define printarr(a , n) for(int i = 0 ; i < n  ;i ++) cout << a[i] << " "; cout << endl;
#define endl '\n'
#define sq(a) (a)*(a)
#define yes  cout << "YES" << endl;
#define no  cout << "NO" << endl;


#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
  
#define ordered_set tree<int, null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>
#define inf 1e18

int rand(int l, int r){
 	static mt19937 
 	rng(chrono::steady_clock::now().time_since_epoch().count());
 	uniform_int_distribution<int> ludo(l, r); 
 	return ludo(rng);
}

/*
	order_of_key(x) -> number of elements strictly smaller than x
	find_by_order(k) -> kth element 
	Good Life Good Wife
*/

struct node
{
	ll l , r;
	ll sum;
	ll lazy;
	struct node * lft , *rgt;
} *headnode;


struct node* newnode(ll left , ll right)
{
	struct node *nn = new node();
	nn -> l = left;
	nn -> r = right;
	nn -> sum = 0;
	nn -> lazy = 0;
	return nn;
}


void createchild(struct node *cur)
{
	ll l = cur->l;
	ll r = cur->r;
	ll m = (l + r)/2;
	cur -> lft = newnode(l , m);
	cur -> rgt = newnode(m+1,r);
}

void propagate(struct node *cur)
{
	ll sz = cur->r - cur->l + 1;
	if(sz == 1)
	{
		cur->sum += sz*(cur->lazy);
		cur->lazy = 0ll;
	}
	else
	{
		if(cur->lft == NULL || cur->rgt == NULL)
			createchild(cur);

		cur->lft->lazy += cur->lazy;
		cur->rgt->lazy += cur->lazy;
		cur->lft->lazy %= (1<<30);
		cur->rgt->lazy %= (1<<30);
		cur->sum += sz*(cur->lazy);
		cur->lazy = 0ll;
	}

	cur->sum %= (1<<30);
}

void addlazy(ll a , ll b , ll v , struct node *cur)
{
	propagate(cur);

	if(cur->l >= a && cur->r <= b)
	{	
		cur->lazy += v;
		cur->lazy %= (1<<30);
		return;
	}

	if(cur->l > b || cur->r < a)
	{
		return ;
	}

	if(cur->lft == NULL || cur->rgt == NULL)
		createchild(cur);
	
	addlazy(a , b , v, cur->lft);
	addlazy(a , b , v, cur->rgt);
	propagate(cur->lft);
	propagate(cur->rgt);
	cur->sum = cur->lft->sum + cur->rgt->sum;
	cur->sum %= (1ll<<30);
}



ll getsum(ll a , ll b , struct node *cur)
{
	propagate(cur);

	if(cur->l >= a && cur->r <= b)
	{	
		return cur->sum;
	}

	if(cur->l > b || cur->r < a)
	{
		return 0ll;
	}

	if(cur->lft == NULL || cur->rgt == NULL)
	createchild(cur);

	return (getsum(a , b , cur->lft) +  getsum(a, b , cur->rgt))%(1<<30);
}


void solve()
{
	ll n , m;
	cin >> n >> m;

	headnode = newnode(0 , (1ll << m)-1);

	vl p(n+1);
	vl q(n+1);
	ll x = 0;
	ll mod = (1ll << m);

	for(int i = 1 ; i <= n ; i ++)
	{
		cin >> p[i] >> q[i];
		
		ll a = p[i] + x , b = q[i] + x;
		a %= mod;
		b %= mod;

		if(a > b) swap(a , b);

		addlazy(a , b , i , headnode);
		x += getsum(a , b , headnode);

	//	cout << a << " " << b << " = " << x << endl;
		x %= (1ll<<30);	
	}

	cout << x << endl;
	
}
int main(){

	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	

	#ifndef ONLINE_JUDGE
		freopen("input.txt", "r" , stdin);
		freopen("output.txt", "w" , stdout);
	#endif

	int t=1;
	for(int i = 1 ; i <= t ; i ++)
	{
    	solve();
	}	
	return 0;
}