Submission #1604090

---

Source Code Expand

// #include {{{
#include <array>
#include <vector>
#include <deque>
#include <queue>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <string>
#include <algorithm>
#include <numeric>
#include <functional>
#include <iterator>
#include <tuple>
#include <utility>
#include <random>
#include <limits>
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <cstdint>
#include <cassert>
// }}}

using namespace std;

// macros {{{
template<typename T, size_t N>
constexpr size_t NELEMS(T (&)[N]) { return N; }

template<typename InputIt>
void PRINT_RANGE(InputIt first, InputIt last)
{
    for(; first != last; ++first)
        cout << *first << (first==last ? "" : " ");
    cout << "\n";
}

template<typename T>
void PRINT_MATRIX(T mat, size_t nr, size_t nc)
{
    for(size_t r = 0; r < nr; ++r) {
        for(size_t c = 0; c < nc; ++c) {
            cout << mat[r][c] << (c==nc-1 ? "" : " ");
        }
        cout << "\n";
    }
}

#define FOR(i, start, end) for(int i = (start); i < (end); ++i)
#define REP(i, n) FOR(i, 0, n)
// }}}

// types {{{
using ll  = long long;
using ull = unsigned long long;
// }}}

template<typename T>
T ceilpow2(T n)
{
    assert(n >= 0);
    if(n == 0) return T(1);

    int r = static_cast<int>(floor(log2(n))) + 1;
    return T(1) << r;
}

template<typename T>
T floorpow2(T n)
{
    assert(n >= 0);
    if(n == 0) return T(1);

    int r = static_cast<int>(floor(log2(n)));
    return T(1) << r;
}

ull A, B;

void solve()
{
    if(A == B) {
        cout << 1 << "\n";
        return;
    }

    ull T2 = ceilpow2(A ^ B);
    A &= T2-1;
    B &= T2-1;
    ull T = T2 >> 1;

    ull xmin = A;
    ull xmax = T-1;

    ull K = ceilpow2(B & (T-1));

    ull ymin = T;
    ull ymax = T + K - 1;

    ull xymin = T+A;
    ull xymax = 2*T - 1;

#ifdef DEBUG
    cout << "T:" << T << "\n";
    cout << "K:" << K << "\n";
#endif

    ull ans = xmax - xmin + 1;
    if(ymax < xymin) {
        ans += ymax  - ymin  + 1;
        ans += xymax - xymin + 1;
    }
    else {
        ans += xymax - ymin + 1;
    }

    cout << ans << "\n";
}

int main()
{
    cin >> A >> B;

    solve();

    return 0;
}

Submission Info

Judge Result