oj.uz

답안 #251623

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
251623 2020-07-22T03:56:47 Z abacaba Pipes (BOI13_pipes) C++14
100 / 100
 251 ms 43372 KB 
#include <iostream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <cstring>
#include <chrono>
#include <vector>
#include <map>
#include <random>
#include <set>
#include <algorithm>
#include <math.h>
#include <cstdio>
#include <stdio.h>
#include <queue>
#include <bitset>
#include <cstdlib>
#include <deque>
#include <cassert>
#include <stack>
using namespace std;
 
#define mp make_pair
#define f first
#define se second
#define pb push_back
#define ppb pop_back
#define emb emplace_back
#define ll long long
#define ull unsigned long long
#define cntbit(x) __builtin_popcount(x)
#define endl '\n'
#define uset unordered_set
#define umap unordered_map
#define pii pair<int, int>
#define ld long double
#define pll pair<long long, long long>
 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
template <typename T> inline T range(T l, T r) {
    return uniform_int_distribution<T>(l, r)(rng);
}
 
inline void setin(string s) {
    freopen(s.c_str(), "r", stdin);
}
 
inline void setout(string s) {
    freopen(s.c_str(), "w", stdout);
}
 
template <typename T> void Min(T &a, T b) {
    a = min(a, b);
}
 
template <typename T> void Max(T &a, T b) {
    a = max(a, b);
}
 
#define int long long
 
const int mod = 1e9 + 7;
const int inf = 2e9;
const int N = 5e5 + 15;
int n, m, a[N];
vector <int> g[N];
bool used[N];
 
set <pii> cur;
int deg[N], d[N];
 
int p[N], sz[N];
pii e[N];

int pp[N];
int ans[N];
 
int pref[2][N];

int cnt;

vector <int> now;

int find(int v) {
    if(v == p[v])
        return v;
    return p[v] = find(p[v]);
}
 
void unio(int a, int b) {
    a = find(a);
    b = find(b);
    if(a != b) {
        if(sz[a] < sz[b])
            swap(a, b);
        p[b] = a;
        sz[a] += sz[b];
    }
}
 
inline int gt(int i, int v) {
    return e[i].f == v ? e[i].se : e[i].f;
}
 
void precheck(int v) {
    used[v] = true;
    for(int ind : g[v]) {
        int to = gt(ind, v);
        if(to == pp[v])
            continue;
        if(used[to]) {
            if(d[to] > d[v])
                continue;
            if((d[v] - d[to]) & 1) {
                cout << 0 << endl;
                exit(0);
            }
            ++cnt;
            if(cnt > 1) {
                cout << 0 << endl;
                exit(0);
            }
            int u = v;
            while(u != to) {
                unio(u, pp[u]);
                u = pp[u];
            }
            u = v;
            while(u != pp[to]) {
                now.pb(u);
                u = pp[u];
            }
        }
        else {
            d[to] = d[v] + 1;
            pp[to] = v;
            precheck(to);
        }
    }
}

inline int get(int k, int l, int r) {
    k = (k + 10) & 1;
    Max(l, 0LL);
    if(l > r)
        return 0;
    return pref[k][r] - (l == 0 ? 0 : pref[k][l-1]);
}
 
void solve_for_cycle() {
    if(now.empty())
        return;
    int sum = 0;
    for(int v : now)
        sum += a[v];
    for(int i = 0; i < now.size(); ++i) {
        for(int j = 0; j < 2; ++j)
            pref[j][i] = (i == 0 ? 0 : pref[j][i-1]);
        pref[i & 1][i] += a[now[i]];
    }
    for(int i = 0; i + 1 < now.size(); ++i) {
        int v = now[i];
        int ind = -1;
        for(int j = 0; j < g[v].size(); ++j)
            if(gt(g[v][j], v) == now[i + 1])
                ind = g[v][j];
        // if(ind == -1) {
        //     cout << "ASdasd" << endl;
        //     exit(0);
        // }
        assert(ind != -1);
        int val = get(i + 2, i + 2, now.size() - 1) + get(i - 1, 0, i - 1);
        ans[ind] = sum - 2 * val;
    }
    int v = now.back();
    int ind = -1;
    for(int j = 0; j < g[v].size(); ++j)
        if(gt(g[v][j], v) == now[0])
            ind = g[v][j];
    // if(ind == -1) {
    //     cout << "ASdasd" << endl;
    //     exit(0);
    // }
    assert(ind != -1);
    int val = get(1, 1, now.size() - 2);
    ans[ind] = sum - 2 * val;
}
 
main() {
    for(int i = 0; i < N; ++i)
        p[i] = i, sz[i] = 1;
    ios_base::sync_with_stdio(0); cout.tie(0); cin.tie(0);
    // setin("input.txt");
    cin >> n >> m;
    for(int i = 1; i <= n; ++i)
        cin >> a[i];
    for(int i = 1; i <= m; ++i) {
        cin >> e[i].f >> e[i].se;
        g[e[i].f].pb(i);
        g[e[i].se].pb(i);
    }
    precheck(1);
    for(int i = 1; i <= n; ++i)
        deg[i] = g[i].size(), cur.insert({g[i].size(), i});
    memset(used, 0, sizeof(used));
    while(!cur.empty()) {
        int v = cur.begin()->se;
        cur.erase(cur.begin());
        used[v] = true;
        for(int ind : g[v]) {
            int to = gt(ind, v);
            if(used[to] && deg[to] == 1)
                a[v] -= ans[ind] / 2;
        }
        if(deg[v] != 1)
            continue;
        for(int ind : g[v]) {
            int to = gt(ind, v);
            if(used[to])
                continue;
            ans[ind] = 2 * a[v];
            cur.erase({deg[to], to});
            --deg[to];
            cur.insert({deg[to], to});
        }
    }
    memset(used, 0, sizeof(used));
    solve_for_cycle();
    for(int i = 1; i <= m; ++i)
        cout << ans[i] << endl;
    return 0;
}

Compilation message

pipes.cpp: In function 'void solve_for_cycle()':
pipes.cpp:157:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < now.size(); ++i) {
                    ~~^~~~~~~~~~~~
pipes.cpp:162:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i + 1 < now.size(); ++i) {
                    ~~~~~~^~~~~~~~~~~~
pipes.cpp:165:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[v].size(); ++j)
                        ~~^~~~~~~~~~~~~
pipes.cpp:178:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int j = 0; j < g[v].size(); ++j)
                    ~~^~~~~~~~~~~~~
pipes.cpp: At global scope:
pipes.cpp:190:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 11 ms 20480 KB Output is correct
2 Correct 11 ms 20480 KB Output is correct
3 Correct 12 ms 20608 KB Output is correct
4 Correct 210 ms 36472 KB Output is correct
5 Correct 11 ms 20480 KB Output is correct
6 Correct 11 ms 20480 KB Output is correct
7 Correct 11 ms 20480 KB Output is correct
8 Correct 14 ms 20480 KB Output is correct
9 Correct 13 ms 20608 KB Output is correct
10 Correct 12 ms 20608 KB Output is correct
11 Correct 14 ms 20736 KB Output is correct
12 Correct 12 ms 20608 KB Output is correct
13 Correct 189 ms 33144 KB Output is correct
14 Correct 210 ms 35448 KB Output is correct
15 Correct 195 ms 36344 KB Output is correct
16 Correct 153 ms 33912 KB Output is correct
17 Correct 192 ms 36344 KB Output is correct
18 Correct 193 ms 36344 KB Output is correct
19 Correct 251 ms 38904 KB Output is correct
20 Correct 13 ms 20480 KB Output is correct
21 Correct 12 ms 20608 KB Output is correct
22 Correct 192 ms 36344 KB Output is correct
23 Correct 142 ms 33104 KB Output is correct
24 Correct 202 ms 36440 KB Output is correct
25 Correct 156 ms 33656 KB Output is correct

Subtask #2
70.0 / 70.0

# 결과 실행 시간 메모리 Grader output
1 Correct 11 ms 20480 KB Output is correct
2 Correct 12 ms 20736 KB Output is correct
3 Correct 72 ms 29816 KB Output is correct
4 Correct 80 ms 32632 KB Output is correct
5 Correct 62 ms 27384 KB Output is correct
6 Correct 248 ms 43024 KB Output is correct
7 Correct 15 ms 20480 KB Output is correct
8 Correct 11 ms 20420 KB Output is correct
9 Correct 12 ms 19968 KB Output is correct
10 Correct 11 ms 19968 KB Output is correct
11 Correct 11 ms 19968 KB Output is correct
12 Correct 11 ms 19968 KB Output is correct
13 Correct 11 ms 19968 KB Output is correct
14 Correct 13 ms 20480 KB Output is correct
15 Correct 12 ms 20736 KB Output is correct
16 Correct 12 ms 20608 KB Output is correct
17 Correct 12 ms 20096 KB Output is correct
18 Correct 11 ms 20096 KB Output is correct
19 Correct 13 ms 20096 KB Output is correct
20 Correct 12 ms 20096 KB Output is correct
21 Correct 11 ms 20096 KB Output is correct
22 Correct 12 ms 20608 KB Output is correct
23 Correct 128 ms 37616 KB Output is correct
24 Correct 196 ms 40756 KB Output is correct
25 Correct 69 ms 29816 KB Output is correct
26 Correct 80 ms 31736 KB Output is correct
27 Correct 80 ms 31992 KB Output is correct
28 Correct 82 ms 26488 KB Output is correct
29 Correct 178 ms 38520 KB Output is correct
30 Correct 205 ms 42104 KB Output is correct
31 Correct 169 ms 43372 KB Output is correct
32 Correct 241 ms 37748 KB Output is correct
33 Correct 90 ms 30840 KB Output is correct
34 Correct 99 ms 31212 KB Output is correct
35 Correct 83 ms 32632 KB Output is correct
36 Correct 60 ms 27568 KB Output is correct
37 Correct 237 ms 43128 KB Output is correct
38 Correct 172 ms 41584 KB Output is correct
39 Correct 202 ms 37076 KB Output is correct
40 Correct 169 ms 40308 KB Output is correct
41 Correct 79 ms 32632 KB Output is correct
42 Correct 84 ms 31476 KB Output is correct
43 Correct 112 ms 32888 KB Output is correct
44 Correct 72 ms 27424 KB Output is correct
45 Correct 216 ms 39928 KB Output is correct
46 Correct 169 ms 42732 KB Output is correct
47 Correct 170 ms 40308 KB Output is correct
48 Correct 148 ms 43112 KB Output is correct
49 Correct 88 ms 28024 KB Output is correct
50 Correct 81 ms 31224 KB Output is correct
51 Correct 107 ms 29688 KB Output is correct
52 Correct 69 ms 28152 KB Output is correct
53 Correct 196 ms 39800 KB Output is correct
54 Correct 203 ms 40852 KB Output is correct