#include<iostream>
using namespace std;
//1-indexed
#include<vector>
template<typename T>
struct BIT{
	int n;
	vector<T>bit;
	BIT(int n_=0):n(n_),bit(n_+1){}
	T sum(int i)
	{
		T ans=0;
		for(;i>0;i-=i&-i)ans+=bit[i];
		return ans;
	}
	void add(int i,T a)
	{
		if(i==0)return;
		for(;i<=n;i+=i&-i)bit[i]+=a;
	}
	int lower_bound(T k)//k<=sum(ret)
	{
		if(k<=0)return 0;
		int ret=0,i=1;
		while((i<<1)<=n)i<<=1;
		for(;i;i>>=1)
			if(ret+i<=n&&bit[ret+i]<k)k-=bit[ret+=i];
		return ret+1;
	}
};
int N,M;
int id[2<<17];
int L[1<<17];
main()
{
	cin>>N>>M;
	for(int i=1;i<=N;i++)
	{
		int a,b;cin>>a>>b;
		if(a>b)a^=b^=a^=b;
		L[i]=a;
		id[a]=i;
		id[b]=-i;
	}
	long ans=0;
	BIT<int>P(M);
	for(int i=0;i<M;i++)
	{
		if(id[i]>0)P.add(i+1,1);
		else
		{
			P.add(L[-id[i]]+1,-1);
			ans+=P.sum(i+1)-P.sum(L[-id[i]]);
		}
	}
	cout<<ans<<endl;
}