#include using namespace std; #define rep(i,n) for(ll i=0;i=0;i--) #define perl(i,r,l) for(ll i=r-1;i>=l;i--) #define fi first #define se second #define ins insert #define pqueue(x) priority_queue,greater> #define all(x) (x).begin(),(x).end() #define CST(x) cout<; using vvl=vector>; using pl=pair; using vpl=vector; using vvpl=vector; const ll MOD=1000000007; const ll MOD9=998244353; const int inf=1e9+10; const ll INF=4e18; const ll dy[8]={0,-1,0,1}; const ll dx[4]={-1,0,1,0}; template inline bool chmax(T &a, T b) { return ((a < b) ? (a = b, true) : (false)); } template inline bool chmin(T &a, T b) { return ((a > b) ? (a = b, true) : (false)); } using ull=unsigned long long; int main(){ ll n;cin >> n; ll m=1563; ull dp[m];rep(i,m)dp[i]=0;dp[0]=1; rep(_,n){ ll l,r;cin >> l >> r; bool flag=false; rep(i,m){ if(flag)break; if(((i+1)<<6)-1>j&1){ if(((i<<6)|j)>=r){ dp[i]^=1LL<>63&1)dp[i+1]|=1; dp[i]<<=1; } else if(((i+1)<<6)<=l||r<=(i<<6))continue; else{ ll ns=0; rep(j,63){ if(dp[i]>>j&1){ if(l<=((i<<6)|j)&&((i<<6)|j)>63&1)if(((i<<6)|63)>6]|=1LL<<(l&63); //cout << bitset<64>(dp[1]) << bitset<64>(dp[0]) << endl; } ll ans=0; rep(i,m)ans+=__builtin_popcountl(dp[i]); cout << ans-1 << endl; }