Submission #20145843

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Source Code Expand

#include <algorithm>
#include <cassert>
#include <chrono>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <vector>
#include <variant>
#include <sstream>
#include <memory>

using namespace std;

#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define reunique(v) v.resize(std::unique(v.begin(), v.end()) - v.begin())
#define sz(v) ((int)(v).size())

#define vec1d(x) vector<x>
#define vec2d(x) vector<vec1d(x)>
#define vec3d(x) vector<vec2d(x)>
#define vec4d(x) vector<vec3d(x)>

#define ivec1d(x, n, v) vec1d(x)(n, v)
#define ivec2d(x, n, m, v) vec2d(x)(n, ivec1d(x, m, v))
#define ivec3d(x, n, m, k, v) vec3d(x)(n, ivec2d(x, m, k, v))
#define ivec4d(x, n, m, k, l, v) vec4d(x)(n, ivec3d(x, m, k, l, v))

#ifdef LOCAL
#include "pretty_print.h"
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: ", debug_out(__VA_ARGS__)
#else
#define dbg(...) 42
#endif

#define nl "\n"

typedef long double ld;
typedef long long ll;
typedef unsigned long long ull;

template <typename T> T sqr(T x) { return x * x; }
template <typename T> T abs(T x) { return x < 0? -x : x; }
template <typename T> T gcd(T a, T b) { return b? gcd(b, a % b) : a; }
template <typename T> bool chmin(T &x, const T& y) { if (x > y) { x = y; return true; } return false; }
template <typename T> bool chmax(T &x, const T& y) { if (x < y) { x = y; return true; } return false; }

auto random_address = [] { char *p = new char; delete p; return (uint64_t) p; };
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count() * (random_address() | 1));
mt19937_64 rngll(chrono::steady_clock::now().time_since_epoch().count() * (random_address() | 1));


typedef pair<ll, ll> pll;


vector<pll> get(ll b, ll c) {
    vector<pll> ret;
    ll l = b - c / 2;
    ll r = b;
    ret.push_back({l, r});
    if (c) {
        if (c % 2 == 0) {
            ++l;
        }
        swap(l, r);
        l = -l;
        r = -r;
        ret.push_back({l, r});
    }
    return ret;
}

int main(int /* argc */, const char** /* argv */)
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
#ifdef LOCAL
    assert(freopen("i.txt", "r", stdin));
    assert(freopen("o.txt", "w", stdout));
#endif

    ll b, c;
    while (cin >> b >> c) {
        vector<pll> e;
        vector<pll> fs = get(b, c);
        vector<pll> sc = get(-b, c - 1);
        e.insert(e.end(), all(fs));
        e.insert(e.end(), all(sc));
        sort(all(e));
        ll ans = e[0].second - e[0].first + 1;
        ll last = e[0].second;
        for (int i = 1; i < sz(e); ++i) {
            auto [l, r] = e[i];
            if (l <= last) {
                if (r > last) {
                    ans += r - last;
                    last = r;
                }
            } else {
                ans += r - l + 1;
                last = r;
            }
        }
        cout << ans << nl;
    }

#ifdef LOCAL
    cerr << "Time execute: " << clock() / (double)CLOCKS_PER_SEC << " sec" << endl;
#endif
    return 0;
}

Submission Info

Judge Result