oj.uz

Submission #251612

# Submission time Handle Problem Language Result Execution time Memory
251612 2020-07-22T03:25:48 Z abacaba Pipes (BOI13_pipes) C++14
90.9259 / 100
 276 ms 43128 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];
 
set <int> cycles;
vector <int> inc;
 
int pref[2][N];
 
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, int p = -1) {
    used[v] = true;
    pp[v] = p;
    for(int ind : g[v]) {
        int to = gt(ind, v);
        if(to == p)
            continue;
        if(used[to]) {
            if(d[to] > d[v])
                continue;
            if((d[v] - d[to]) & 1) {
                cout << 0 << endl;
                exit(0);
            }
            int u = v;
            while(u != to) {
                unio(u, pp[u]);
                u = pp[u];
            }
        }
        else {
            d[to] = d[v] + 1;
            precheck(to, v);
        }
    }
}

vector <int> now;
 
void dfs(int v) {
    used[v] = true;
    now.pb(v);
    for(int ind : g[v]) {
        int to = gt(ind, v);
        if(used[to] || find(v) != find(to))
            continue;
        dfs(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() {
    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});
        }
    }
    set <int> is = {};
    for(int i = 1; i <= n; ++i)
        if(sz[find(i)] > 1)
            is.insert(find(i));
    if(is.size() > 1)
        return cout << 0 << endl, 0;
    memset(used, 0, sizeof(used));
    for(int i = 1; i <= n; ++i) {
        if(sz[find(i)] > 1 && !used[i]) {
            now.clear();
            dfs(i);
            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:158:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < now.size(); ++i) {
                    ~~^~~~~~~~~~~~
pipes.cpp:163:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i + 1 < now.size(); ++i) {
                    ~~~~~~^~~~~~~~~~~~
pipes.cpp:166:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[v].size(); ++j)
                        ~~^~~~~~~~~~~~~
pipes.cpp:179:22: 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:191:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory 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 267 ms 36344 KB Output is correct
5 Correct 11 ms 20480 KB Output is correct
6 Correct 11 ms 20480 KB Output is correct
7 Correct 13 ms 20480 KB Output is correct
8 Correct 15 ms 20480 KB Output is correct
9 Correct 14 ms 20608 KB Output is correct
10 Correct 17 ms 20608 KB Output is correct
11 Correct 14 ms 20608 KB Output is correct
12 Correct 12 ms 20608 KB Output is correct
13 Correct 150 ms 33144 KB Output is correct
14 Correct 175 ms 35448 KB Output is correct
15 Correct 240 ms 36400 KB Output is correct
16 Correct 222 ms 33912 KB Output is correct
17 Correct 188 ms 36344 KB Output is correct
18 Correct 244 ms 36472 KB Output is correct
19 Correct 182 ms 38904 KB Output is correct
20 Correct 11 ms 20480 KB Output is correct
21 Correct 12 ms 20608 KB Output is correct
22 Correct 234 ms 36484 KB Output is correct
23 Correct 145 ms 33016 KB Output is correct
24 Correct 276 ms 36348 KB Output is correct
25 Correct 160 ms 33784 KB Output is correct

Subtask #2
60.9259259259 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 20480 KB Output is correct
2 Correct 12 ms 20736 KB Output is correct
3 Correct 68 ms 29816 KB Output is correct
4 Incorrect 165 ms 41592 KB Output isn't correct
5 Correct 163 ms 35448 KB Output is correct
6 Correct 214 ms 43128 KB Output is correct
7 Correct 12 ms 20480 KB Output is correct
8 Correct 12 ms 20480 KB Output is correct
9 Correct 11 ms 19968 KB Output is correct
10 Correct 13 ms 20480 KB Output is correct
11 Incorrect 12 ms 20480 KB Output isn't correct
12 Correct 11 ms 20480 KB Output is correct
13 Correct 11 ms 19968 KB Output is correct
14 Correct 11 ms 20480 KB Output is correct
15 Correct 14 ms 20736 KB Output is correct
16 Correct 14 ms 20608 KB Output is correct
17 Correct 12 ms 20096 KB Output is correct
18 Correct 12 ms 20608 KB Output is correct
19 Incorrect 12 ms 20608 KB Output isn't correct
20 Correct 12 ms 20608 KB Output is correct
21 Correct 12 ms 20096 KB Output is correct
22 Correct 12 ms 20608 KB Output is correct
23 Correct 161 ms 35960 KB Output is correct
24 Correct 219 ms 38912 KB Output is correct
25 Correct 68 ms 29816 KB Output is correct
26 Correct 146 ms 39544 KB Output is correct
27 Incorrect 156 ms 39928 KB Output isn't correct
28 Correct 170 ms 36168 KB Output is correct
29 Correct 177 ms 38520 KB Output is correct
30 Correct 181 ms 40568 KB Output is correct
31 Correct 220 ms 42720 KB Output is correct
32 Correct 213 ms 36856 KB Output is correct
33 Correct 72 ms 30840 KB Output is correct
34 Correct 135 ms 39032 KB Output is correct
35 Incorrect 177 ms 41464 KB Output isn't correct
36 Correct 161 ms 35832 KB Output is correct
37 Correct 268 ms 43020 KB Output is correct
38 Correct 204 ms 41328 KB Output is correct
39 Correct 193 ms 36984 KB Output is correct
40 Correct 226 ms 38596 KB Output is correct
41 Correct 78 ms 32632 KB Output is correct
42 Correct 114 ms 39256 KB Output is correct
43 Incorrect 148 ms 41976 KB Output isn't correct
44 Correct 168 ms 35448 KB Output is correct
45 Correct 192 ms 39728 KB Output is correct
46 Correct 197 ms 41336 KB Output is correct
47 Correct 196 ms 38776 KB Output is correct
48 Correct 230 ms 42616 KB Output is correct
49 Correct 83 ms 28152 KB Output is correct
50 Correct 207 ms 39032 KB Output is correct
51 Incorrect 196 ms 37624 KB Output isn't correct
52 Correct 166 ms 36732 KB Output is correct
53 Correct 238 ms 39800 KB Output is correct
54 Correct 204 ms 40576 KB Output is correct