#include "bits/stdc++.h"
using namespace std;
#define int long long
#define FOR(i, a, b) for(int i=(a);i<(b);i++)
#define RFOR(i, a, b) for(int i=(b-1);i>=(a);i--)
#define REP(i, n) for(int i=0; i<(n); i++)
#define RREP(i, n) for(int i=(n-1); i>=0; i--)
#define ALL(a) (a).begin(),(a).end()
#define UNIQUE_SORT(l) sort(ALL(l)); l.erase(unique(ALL(l)), l.end());
#define CONTAIN(a, b) find(ALL(a), (b)) != (a).end()
#define array2(type, x, y) array<array<type, y>, x>
#define vector2(type) vector<vector<type> >
#define out(...) printf(__VA_ARGS__)

int dxy[] = {0, 1, 0, -1, 0};

void solve();
signed main()
{
#if DEBUG
    std::ifstream in("input.txt");
    std::cin.rdbuf(in.rdbuf());
#endif
    cin.tie(0);
    ios::sync_with_stdio(false);
    solve();
    return 0;
}

/*================================*/

int N,M,Q;

void solve() {
    cin>>N>>M;
    int a,b;
    vector<int> AB(M, -1);
    vector<int> BA(M, -1);
    vector<int> S;
    REP(i,N) {
        cin>>a>>b;
        if (a>b) swap(a,b);
        AB[a]=b;
        BA[b]=a;
    }
    int ans = 0;
    REP(m,M) {
        if (BA[m]>-1) {
            auto it = lower_bound(S.begin(), S.end(), BA[m]);
            ans += (S.end() - it - 1);
            S.erase(it);
        }
        if (AB[m]>-1) S.push_back(m);
    }
    
    cout << ans << endl;
}