#include<bits/stdc++.h>
#define L(i, j, k) for(int i = (j); i <= (k); ++i)
#define R(i, j, k) for(int i = (j); i >= (k); --i)
#define ll long long
#define vi vector <int>
#define sz(a) ((int) (a).size())
#define me(f, x) memset(f, x, sizeof(f))
#define ull unsigned long long
#define pb emplace_back
using namespace std; 
const int N = 1e6 + 7;
const int B = 123;
template < int N > struct fenwt {
	using F = long long ;
	F a[N + 1];
	void add (int x, F w) {
		for (; x <= N; x += x & -x) a[x] += w;
	}
	F query (int x) {
		F ret = 0;
		for (; x; x -= x & -x) ret += a[x];
		return ret;
	}
	F get (int l, int r) {
		if(l > r) return 0;
		return query (r) - query (l - 1);
	}
} ;
fenwt < N > F[3];
int n, D, L;
struct node {
	int slv;
	int tim;
	int id;
	int o;
} P[N];
int col[N];
vi vc[N][3];
vi pr[N];
void init() {
	int pn = 0;
	L(i, 1, n) {
		if(sz(pr[i])) {
			swap(pr[i], pr[++pn]);
		}
	}
	n = pn;
}
ll dp[N];
ll ans;
vi dra[N];
fenwt<N>fs;
ll sl[N], sr[N];
int vis[N];
ll sp[N];
int ap[N], tot;
int main() {
	// freopen("data.txt","r",stdin);
	ios :: sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	cin >> n >> D >> L;
	L(i, 1, n) {
		int d, t;
		cin >> d >> t;
		pr[d].pb(t);
	}
	n = D;
	L(i, 1, n) sort(pr[i].begin(), pr[i].end());
	init();
	L(i, 1, n) {
		{
		++tot;
		P[tot].slv = 1;
		P[tot].tim = pr[i].back() + (sz(pr[i]) - 1) * 20;
		P[tot].id = i;
		P[tot].o = 2;
		}
		if(sz(pr[i]) >= 2) {
		++tot;
		if(sz(pr[i]) >= 3) {
			P[tot].slv = 3;
			P[tot].tim = pr[i][0] + pr[i][1] + pr[i][2];
		} else if(sz(pr[i]) == 2) {
			P[tot].slv = 2;
			P[tot].tim = pr[i][0] + pr[i][1];
		}
		P[tot].id = i;
		P[tot].o = 0;
		}
		{
		++tot;
		P[tot].slv = 1;
		P[tot].tim = pr[i][0];
		P[tot].id = i;
		P[tot].o = 1;
		}
		if(sz(pr[i]) >= 2) {
		++tot;
		P[tot].slv = 2;
		P[tot].tim = pr[i][sz(pr[i]) - 2] + pr[i][sz(pr[i]) - 1] + (sz(pr[i]) - 2) * 20;
		P[tot].id = i;
		P[tot].o = 1;
		}
	}
	sort(P + 1, P + tot + 1, [&] (node a, node b) {
		if(a.slv != b.slv) return a.slv < b.slv;
		if(a.tim != b.tim) return a.tim > b.tim;
		return a.o > b.o;
	});
	L(i, 1, tot) {
		col[i] = P[i].id;
		if(P[i].o == 2) {
			dp[i] = 1;
		} else {
			int lst = 0;
			if(sz(vc[col[i]][P[i].o]))lst = vc[col[i]][P[i].o].back();
			dp[i] = F[P[i].o + 1].query(i - 1) - F[P[i].o + 1].query(lst);
			for(auto&j : vc[col[i]][P[i].o + 1])
				if(lst <= j)
					dp[i] -= dp[j];
		}
		F[P[i].o].add(i, dp[i]);
		vc[col[i]][P[i].o].pb(i);
		if(P[i].o == 0) {
			ans += dp[i];
		}
		// cout << col[i] << ' ' << P[i].o << " : " << dp[i] << endl;
	}
	L(i, 1, n) if(sz(vc[i][2]) && sz(vc[i][0])) {
		dra[vc[i][0][0]].pb(vc[i][2][0]);
		int win = 0;
		for(auto&j : vc[i][1])
			if(vc[i][2][0] <= j && j <= vc[i][0][0])
				win = 1;
		if(win)
			++ans;
	}
	L(i, 1, n)vc[i][1].clear();
	L(i, 1, tot) {
		for(auto&j : dra[i]) {
			ans -= fs.query(i) - fs.query(j);
			// cout << j << ' ' << i << endl;
		}
		if(P[i].o == 1) {
			int lst = 0;
			if(sz(vc[col[i]][P[i].o]))lst = vc[col[i]][P[i].o].back();
			if(lst)fs.add(lst, -1);
			fs.add(i, 1);
			// cout << lst << " and " << i << endl;
			vc[col[i]][P[i].o].pb(i);
		}
	}
	// cout<<"ans="<<ans<<endl;
	L += 21;
	L(i, 1, n) {
		int rs = pr[i].back() + (sz(pr[i]) - 1) * 20;
		rs = min(rs, L);
		sr[rs] += 1;
	}
	L(i, 1, n) if(sz(pr[i]) == 1) {
		sl[pr[i][0]] += 1;
	}
	L(i, 1, L) sl[i] += sl[i - 1];
	L(i, 1, L) ans -= sl[i] * sr[i] * 2;
	R(i, L, 1) sr[i] += sr[i + 1];
	L(k, 1, n) {
		tot = 0;
		if(sz(pr[k]) <= B) {
			for(int t = 0; t < sz(pr[k]); ++t) {
				for(int o = 0; o <= t; ++o) {
					int cost = o * 20 + pr[k][t];
					if(cost <= L) {
						ap[++tot] = cost;
					}
				}
			}
			sort(ap + 1, ap + tot + 1);
			tot = unique(ap + 1, ap + tot + 1) - ap - 1;
		} else {
			for(int t = 0; t < sz(pr[k]); ++t) {
				vis[pr[k][t]] += 1;
				ll to = (t + 1) * 20 + pr[k][t];
				if(to <= L)
					vis[to] -= 1;
			}
			L(i, 20, L)
				vis[i] += vis[i - 20];
			L(i, 0, L)
				if(vis[i])
					ap[++tot] = i;
			L(i, 0, L) vis[i] = 0;
		}
		L(i, 1, tot) 
			sp[ap[i]] += 1;
		L(i, 1, tot)
			ans += sl[ap[i]] * sr[ap[i]];
		L(i, 1, tot - 1)
			ans -= sl[ap[i]] * sr[ap[i + 1]];
	} 
	L(i, 1, n) if(sz(pr[i]) == 1) {
		ans -= sp[pr[i][0]];
		ans += 2;
	}
	// L(ls, 1, L) L(rs, ls, L) {
	// 	L(k, 1, n) {
	// 		int win = 0;
	// 		for(int t = 0; t < sz(pr[k]); ++t) {
	// 			for(int o = 0; o <= t; ++o) {
	// 				int cost = o * 20 + pr[k][t];
	// 				if(ls <= cost && cost <= rs) {
	// 					win = 1;
	// 				}
	// 			}
	// 		}
	// 		ans += win * sl[ls] * sr[rs];
	// 	}
	// 	ans -= 2 * sl[ls] * sr[rs];
	// }
	cout << ans << '\n';
	return 0;
}