Language: C++

#include <bits/stdc++.h>
using namespace std;
/*{{{*/  //template
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define rrep(i,n) for(int i=(n)-1;i>=0;i--)
constexpr int INF = numeric_limits<int>::max()/2;
constexpr long long LINF = numeric_limits<long long>::max()/3;
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define all(v) (v).begin(),(v).end()
#define sz(x) (int)(x).size()
#define debug(x) cerr<<#x<<":"<<x<<endl
#define debug2(x,y) cerr<<#x<<","<<#y":"<<x<<","<<y<<endl
//struct fin{ fin(){ cin.tie(0); ios::sync_with_stdio(false); } } fin_;
struct Double{ double d; explicit Double(double x) : d(x){} };
ostream& operator<<(ostream& os,const Double x){ os << fixed << setprecision(20) << x.d; return os; }
template<typename T> ostream& operator<<(ostream& os,const vector<T>& vec){ os << "["; for(const auto& v : vec){ os << v << ","; } os << "]"; return os; }
template<typename T,typename U> ostream& operator<<(ostream& os, const map<T,U>& mp){ os << "{"; for(auto& p : mp){ os << p << ","; } os << "}"; return os; }
template<typename T,typename U> ostream& operator<<(ostream& os,const pair<T,U>& p){ os << "(" << p.first << ","<< p.second <<")"; return os; }
template<typename T> ostream& operator<<(ostream& os,const set<T>& st){ os<<"{"; for(T v:st) os<<v<<","; os <<"}"; return os; }
template<typename T,typename U> inline void chmax(T &x,U y){ if(y>x) x = y; }
template<typename T,typename U> inline void chmin(T &x,U y){ if(y<x) x = y; }
using ll = long long;
using ull = unsigned long long;
using pii = std::pair<int,int>;
using vi = std::vector<int>;
typedef vector<vi> vvi;
ll gcd(ll a,ll b){ if(b==0) return a; else return gcd(b,a%b); }
constexpr ll TEN(int n) { return (n == 0) ? 1 : 10 * TEN(n - 1); }
//constexpr double eps = 1e-14; 
constexpr double eps = 1e-10; 
constexpr ll mod = 1e9+7;
const int dx[]={1,0,-1,0} ,dy[] = {0,1,0,-1};
/*}}}*/

int main(){
    ll l,r; cin >> l >> r;

    ll three[70];
    three[0] = 1;
    rep(i,70) if(i>0) three[i] = (three[i-1] * 3) % mod;

    ll ans = 0;
    vector<int> full;
    // 全部含まれる
    for(int i=0;i<=60;i++){
        ll xmin = (1LL << i);
        ll xmax = (1LL << (i+1));
        ll ymin = xmin;
        ll ymax = xmax;
        if(L <= xmin && ymax <= R){
            full.push_back(i);
            ans += three[i];
            ans %= mod;
        }
    }

    if(full.size() > 0){
        ll p = full[0];
        if(p > 0){
            ll d = (1LL << p) - L;
            ll now = -1;
            for(int i=60;i>=0;i--){
                if(now == -1 && (d & (1LL << i))){
                    now = 1;
                    ans += three[i];
                    ans %= mod;
                }

                if(now != -1){
                    now += 1;
                }
            }
        }

        {
            ll d = R - (1LL << full[full.size()-1]);
            ll now = -1;
            for(int i=60;i>=0;i--){
                if(now == -1 && (d & (1LL << i))){
                    now = 1;
                    ans += three[i];
                    ans %= mod;
                }

                if(now != -1){
                    now += 1;
                }
            }
        }
    }else{
        int l,r;
        for(int i=0;i<=60;i++){
            if((1LL << i) >= L){
                l = i;
                break;
            }
        }
        for(int i=60;i>=0;i--){
            if((1LL << i) <= R){
                r = i;
                break;
            }
        }

        {
            ll d = (1LL << p) - L;
            ll now = -1;
            for(int i=60;i>=0;i--){
                if(now == -1 && (d & (1LL << i))){
                    now = 1;
                    ans += three[i];
                    ans %= mod;
                }

                if(now != -1){
                    now += 1;
                }
            }

        }
        {
            ll d = (1LL << p) - L;
            ll now = -1;
            for(int i=60;i>=0;i--){
                if(now == -1 && (d & (1LL << i))){
                    now = 1;
                    ans += three[i];
                    ans %= mod;
                }

                if(now != -1){
                    now += 1;
                }
            }

        }
    }
    cout << ans << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:53:12: error: 'L' was not declared in this scope
   53 |         if(L <= xmin && ymax <= R){
      |            ^
a.cc:53:33: error: 'R' was not declared in this scope
   53 |         if(L <= xmin && ymax <= R){
      |                                 ^
a.cc:63:33: error: 'L' was not declared in this scope
   63 |             ll d = (1LL << p) - L;
      |                                 ^
a.cc:79:20: error: 'R' was not declared in this scope
   79 |             ll d = R - (1LL << full[full.size()-1]);
      |                    ^
a.cc:96:30: error: 'L' was not declared in this scope
   96 |             if((1LL << i) >= L){
      |                              ^
a.cc:102:30: error: 'R' was not declared in this scope
  102 |             if((1LL << i) <= R){
      |                              ^
a.cc:109:28: error: 'p' was not declared in this scope
  109 |             ll d = (1LL << p) - L;
      |                            ^
a.cc:109:33: error: 'L' was not declared in this scope
  109 |             ll d = (1LL << p) - L;
      |                                 ^
a.cc:125:28: error: 'p' was not declared in this scope
  125 |             ll d = (1LL << p) - L;
      |                            ^
a.cc:125:33: error: 'L' was not declared in this scope
  125 |             ll d = (1LL << p) - L;
      |                                 ^