#include <bits/stdc++.h>
#define fr first
#define sc second
#define m_p make_pair
using namespace std;
typedef long long ll;
const ll llinf = 1e18;
const int maxn = 4e6 + 100, inf = 1e9 + 100;
pair<pair<ll, bool>, ll> mas[2 * maxn];
pair<ll, ll> arr[maxn];
pair<ll, ll> seg[maxn];
bool arr_all;
int szmas, szarr, szseg, szind;
ll y;
ll ind[maxn];
int val[maxn];
bool good[maxn];
void add_mas(ll l, ll r, ll w) {
mas[szmas++] = {{l, 0}, w};
mas[szmas++] = {{r + 1, 1}, w};
ind[szind++] = w;
}
void add_arr(ll l, ll r) {
arr[szarr++] = {l, r};
}
ll cur;
void add_seg(ll l, ll r) {
seg[szseg++] = {l, r};
cur += r - l + 1;
}
int get_ind(ll w) {
return lower_bound(ind, ind + szind, w) - ind;
}
void add(ll w) {
int id = get_ind(w);
if (good[id])
return;
if (val[id] == 0)
cur++;
val[id]++;
}
void rem(ll w) {
int id = get_ind(w);
if (good[id])
return;
val[id]--;
if (val[id] == 0)
cur--;
}
int main() {
#ifdef ONPC
freopen("a.in", "r", stdin);
freopen("a.out", "w", stdout);
#endif // ONPC
ios::sync_with_stdio(0);
cin.tie(0);
int n;
ll x;
cin >> n >> x >> y;
x /= __gcd(x, y + 1);
for (int i = 0; i < n; i++) {
ll l, r;
cin >> l >> r;
if (r - l < y && l % y <= r % y)
add_mas(l % y, r % y, (l / y) % x);
else {
if (l % y != 0)
add_mas(l % y, y - 1, (l / y) % x), l += y - l % y;
if (r % y != y - 1)
add_mas(0, r % y, (r / y) % x), r -= r % y + 1;
if (l > r)
continue;
l /= y;
r /= y;
if (r - l + 1 >= x)
arr_all = 1;
else
if (l % x <= r % x)
add_arr(l % x, r % x);
else
add_arr(l % x, x - 1), add_arr(0, r % x);
}
}
if (arr_all) {
add_seg(0, x - 1);
} else {
sort(arr, arr + szarr);
ll L = -1, R = -1;
for (int i = 0; i < szarr; i++) {
if (L == -1 || R + 1 < arr[i].fr) {
if (L != -1)
add_seg(L, R);
L = arr[i].fr;
R = arr[i].sc;
} else
R = max(R, arr[i].sc);
}
if (L != -1)
add_seg(L, R);
}
ll ans = 0;
sort(ind, ind + szind);
szind = unique(ind, ind + szind) - ind;
{
int it = 0;
for (int i = 0; i < szind; i++) {
while (it < szseg && seg[it].sc < ind[i])
it++;
if (it < szseg && seg[it].fr <= ind[i])
good[i] = 1;
}
}
sort(mas, mas + szmas);
ll last = 0;
int L = 0, R = 0;
while (L < szmas) {
ans += cur * (mas[L].fr.fr - last);
while (R < szmas && mas[R].fr.fr == mas[L].fr.fr) {
if (mas[R].fr.sc == 0)
add(mas[R].sc);
else
rem(mas[R].sc);
R++;
}
last = mas[L].fr.fr;
L = R;
}
ans += cur * (y - last);
cout << ans << '\n';
}
