#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long int ll;
typedef pair<ll,ll> pll;
typedef long double ld;
ll INF=1e18+1;
ll N,A,B,M;
ll L[1000006],R[1000006];
ll x,y;
vector<pll> S;
vector<pll> V;
ll ans,K;
int main(){
cin>>N>>A>>B;
if((ld)A*(ld)B>(ld)INF)
M=INF;
else
M=A*B;
cin>>x>>y;
cout<<min(y-x+1,M);
return 0;
for(int i=0;i<N;i++){
cin>>L[i]>>R[i];
x=L[i]%M;
y=R[i]%M;
if(y<x){
if(R[i]-L[i]>=M){
V.push_back({0,1});
V.push_back({M,-1});
}
else{
V.push_back({0,1});
V.push_back({y+1,-1});
V.push_back({x,1});
V.push_back({M,-1});
}
}
else{
V.push_back({x,1});
V.push_back({y+1,-1});
}
}
V.push_back({0,0});
V.push_back({M,0});
sort(V.begin(),V.end());
for(pll p:V){
if(!S.empty() and p.first==S.back().first)
S.back().second+=p.second;
else
S.push_back(p);
}
pll q=*S.begin();
for(pll p:S){
if(K)
ans+=p.first-q.first;
K+=p.second;
q=p;
}
cout<<ans;
}
