#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define ALL(v) v.begin(),v.end()
typedef long long ll;
 
#include<bits/stdc++.h>
using namespace std;

const int MOD=998244353;
const int i6=166374059;
const int i2=499122177;

int main(){
  ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
  
  ll l,r,a,b,c;
  cin>>l>>r>>a>>b>>c;
  
  if(c<=a+b){
    ll d=l+a,u=r-b;
    if(u<d){
      cout<<0<<endl;
      return 0;
    }
    d%=MOD,u%=MOD;
    ll ans=0;
    ans=(ans+MOD-u*(u+1)%MOD*(2*u%MOD+1)%MOD*i6%MOD)%MOD;
    ans=(ans+(d-1+MOD)%MOD*d%MOD*((2*d%MOD-1+MOD)%MOD)%MOD*i6%MOD)%MOD;
    ans=(ans+(d+u)%MOD*u%MOD*(u+1)%MOD*i2%MOD)%MOD;
    ans=(ans+MOD-(d+u)%MOD*((d-1+MOD)%MOD)*d%MOD*i2%MOD)%MOD;
    ans=(ans+MOD-(d-1+MOD)%MOD*(u+1)%MOD*((u-d+1+MOD)%MOD)%MOD)%MOD;
    cout<<ans<<endl;
  }
  else{
    cout<<0<<endl;
  }
  
  return 0;
}