oj.uz

Submission #251613

# Submission time Handle Problem Language Result Execution time Memory
251613 2020-07-22T03:30:32 Z abacaba Pipes (BOI13_pipes) C++14
65 / 100
 305 ms 43000 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) {
    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);
            }
            int u = v;
            while(u != to) {
                unio(u, pp[u]);
                u = pp[u];
            }
        }
        else {
            d[to] = d[v] + 1;
            pp[to] = v;
            precheck(to);
        }
    }
}

vector <int> now;

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();
            int deep = i;
            for(int j = 1; j <= n; ++j) {
                if(find(j) == find(i) && d[j] > d[deep])
                    deep = j;
            }
            
            int u = deep;
            while(1) {
                if(pp[u] == -1 || find(u) != find(pp[u]))
                    break;
                now.pb(u);
                u = pp[u];
            }
            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:147:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < now.size(); ++i) {
                    ~~^~~~~~~~~~~~
pipes.cpp:152:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i + 1 < now.size(); ++i) {
                    ~~~~~~^~~~~~~~~~~~
pipes.cpp:155:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[v].size(); ++j)
                        ~~^~~~~~~~~~~~~
pipes.cpp:168:22: 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:180:6: 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 13 ms 20480 KB Output is correct
2 Correct 13 ms 20480 KB Output is correct
3 Correct 12 ms 20608 KB Output is correct
4 Correct 256 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 11 ms 20480 KB Output is correct
8 Correct 11 ms 20480 KB Output is correct
9 Correct 14 ms 20608 KB Output is correct
10 Correct 12 ms 20608 KB Output is correct
11 Correct 12 ms 20608 KB Output is correct
12 Correct 12 ms 20608 KB Output is correct
13 Correct 149 ms 33272 KB Output is correct
14 Correct 184 ms 35448 KB Output is correct
15 Correct 203 ms 36344 KB Output is correct
16 Correct 154 ms 34172 KB Output is correct
17 Correct 203 ms 36344 KB Output is correct
18 Correct 208 ms 36344 KB Output is correct
19 Correct 268 ms 38136 KB Output is correct
20 Correct 14 ms 20480 KB Output is correct
21 Correct 14 ms 20608 KB Output is correct
22 Correct 212 ms 36344 KB Output is correct
23 Correct 145 ms 33016 KB Output is correct
24 Correct 197 ms 36348 KB Output is correct
25 Correct 164 ms 33784 KB Output is correct

Subtask #2
35.0 / 70.0

# Verdict Execution time Memory Grader output
1 Incorrect 11 ms 20480 KB Output isn't correct
2 Incorrect 12 ms 20608 KB Output isn't correct
3 Correct 69 ms 29048 KB Output is correct
4 Incorrect 177 ms 40312 KB Output isn't correct
5 Correct 188 ms 35704 KB Output is correct
6 Correct 237 ms 43000 KB Output is correct
7 Incorrect 11 ms 20480 KB Output isn't correct
8 Incorrect 15 ms 20480 KB Output isn't correct
9 Correct 12 ms 19968 KB Output is correct
10 Correct 11 ms 20480 KB Output is correct
11 Incorrect 11 ms 20504 KB Output isn't correct
12 Correct 11 ms 20480 KB Output is correct
13 Correct 11 ms 19968 KB Output is correct
14 Incorrect 11 ms 20480 KB Output isn't correct
15 Incorrect 12 ms 20608 KB Output isn't correct
16 Incorrect 13 ms 20608 KB Output isn't correct
17 Correct 12 ms 20096 KB Output is correct
18 Correct 12 ms 20608 KB Output is correct
19 Incorrect 12 ms 20592 KB Output isn't correct
20 Correct 12 ms 20552 KB Output is correct
21 Correct 12 ms 20096 KB Output is correct
22 Incorrect 12 ms 20608 KB Output isn't correct
23 Incorrect 141 ms 35152 KB Output isn't correct
24 Incorrect 162 ms 38008 KB Output isn't correct
25 Correct 72 ms 29056 KB Output is correct
26 Correct 132 ms 38520 KB Output is correct
27 Incorrect 132 ms 38648 KB Output isn't correct
28 Correct 164 ms 36088 KB Output is correct
29 Correct 192 ms 38776 KB Output is correct
30 Incorrect 208 ms 39288 KB Output isn't correct
31 Incorrect 136 ms 40828 KB Output isn't correct
32 Incorrect 185 ms 36600 KB Output isn't correct
33 Correct 71 ms 29944 KB Output is correct
34 Correct 177 ms 38136 KB Output is correct
35 Incorrect 147 ms 40184 KB Output isn't correct
36 Correct 170 ms 35960 KB Output is correct
37 Correct 305 ms 43000 KB Output is correct
38 Incorrect 163 ms 39672 KB Output isn't correct
39 Incorrect 222 ms 36532 KB Output isn't correct
40 Incorrect 223 ms 37880 KB Output isn't correct
41 Correct 110 ms 31224 KB Output is correct
42 Correct 122 ms 38324 KB Output is correct
43 Incorrect 159 ms 40440 KB Output isn't correct
44 Correct 169 ms 35448 KB Output is correct
45 Correct 167 ms 39672 KB Output is correct
46 Incorrect 169 ms 39800 KB Output isn't correct
47 Incorrect 198 ms 38008 KB Output isn't correct
48 Incorrect 153 ms 40696 KB Output isn't correct
49 Correct 78 ms 27896 KB Output is correct
50 Correct 187 ms 38264 KB Output is correct
51 Incorrect 175 ms 37240 KB Output isn't correct
52 Correct 157 ms 36472 KB Output is correct
53 Correct 187 ms 39804 KB Output is correct
54 Incorrect 170 ms 38956 KB Output isn't correct