Submission #251618

# Submission time Handle Problem Language Result Execution time Memory
251618 2020-07-22T03:37:37 Z abacaba Pipes (BOI13_pipes) C++14
90.9259 / 100
302 ms 110188 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];
 
vector <int> cycle[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];
            }
            u = v;
            while(u != pp[to]) {
                cycle[find(u)].pb(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 = cycle[find(i)];
            solve_for_cycle();
            break;
        }
    }
    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:153:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < now.size(); ++i) {
                    ~~^~~~~~~~~~~~
pipes.cpp:158:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i + 1 < now.size(); ++i) {
                    ~~~~~~^~~~~~~~~~~~
pipes.cpp:161:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[v].size(); ++j)
                        ~~^~~~~~~~~~~~~
pipes.cpp:174:22: 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:186:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
# Verdict Execution time Memory Grader output
1 Correct 20 ms 32256 KB Output is correct
2 Correct 22 ms 32256 KB Output is correct
3 Correct 19 ms 32384 KB Output is correct
4 Correct 200 ms 48064 KB Output is correct
5 Correct 18 ms 32128 KB Output is correct
6 Correct 21 ms 32128 KB Output is correct
7 Correct 18 ms 32256 KB Output is correct
8 Correct 21 ms 32128 KB Output is correct
9 Correct 19 ms 32384 KB Output is correct
10 Correct 25 ms 32384 KB Output is correct
11 Correct 21 ms 32384 KB Output is correct
12 Correct 21 ms 32384 KB Output is correct
13 Correct 165 ms 44792 KB Output is correct
14 Correct 205 ms 47224 KB Output is correct
15 Correct 226 ms 48120 KB Output is correct
16 Correct 235 ms 45692 KB Output is correct
17 Correct 273 ms 48120 KB Output is correct
18 Correct 209 ms 48248 KB Output is correct
19 Correct 222 ms 50636 KB Output is correct
20 Correct 18 ms 32128 KB Output is correct
21 Correct 22 ms 32384 KB Output is correct
22 Correct 264 ms 48120 KB Output is correct
23 Correct 216 ms 44792 KB Output is correct
24 Correct 236 ms 48248 KB Output is correct
25 Correct 213 ms 45432 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 20 ms 32256 KB Output is correct
2 Correct 18 ms 32384 KB Output is correct
3 Correct 82 ms 41580 KB Output is correct
4 Runtime error 235 ms 108820 KB Execution killed with signal 11 (could be triggered by violating memory limits)
5 Correct 171 ms 47352 KB Output is correct
6 Correct 222 ms 54776 KB Output is correct
7 Correct 21 ms 32256 KB Output is correct
8 Correct 17 ms 32256 KB Output is correct
9 Correct 21 ms 31744 KB Output is correct
10 Correct 18 ms 32256 KB Output is correct
11 Runtime error 59 ms 65016 KB Execution killed with signal 11 (could be triggered by violating memory limits)
12 Correct 17 ms 32256 KB Output is correct
13 Correct 20 ms 31744 KB Output is correct
14 Correct 17 ms 32256 KB Output is correct
15 Correct 21 ms 32384 KB Output is correct
16 Correct 18 ms 32384 KB Output is correct
17 Correct 17 ms 31744 KB Output is correct
18 Correct 21 ms 32384 KB Output is correct
19 Runtime error 52 ms 65400 KB Execution killed with signal 11 (could be triggered by violating memory limits)
20 Correct 21 ms 32384 KB Output is correct
21 Correct 18 ms 31904 KB Output is correct
22 Correct 20 ms 32384 KB Output is correct
23 Correct 167 ms 49392 KB Output is correct
24 Correct 178 ms 52340 KB Output is correct
25 Correct 73 ms 41592 KB Output is correct
26 Correct 154 ms 51780 KB Output is correct
27 Incorrect 152 ms 53868 KB Output isn't correct
28 Correct 181 ms 48248 KB Output is correct
29 Correct 212 ms 50296 KB Output is correct
30 Correct 191 ms 53744 KB Output is correct
31 Correct 157 ms 55148 KB Output is correct
32 Correct 265 ms 49396 KB Output is correct
33 Correct 79 ms 42488 KB Output is correct
34 Correct 133 ms 50936 KB Output is correct
35 Runtime error 251 ms 108688 KB Execution killed with signal 11 (could be triggered by violating memory limits)
36 Correct 211 ms 47920 KB Output is correct
37 Correct 302 ms 54776 KB Output is correct
38 Correct 179 ms 53360 KB Output is correct
39 Correct 232 ms 48888 KB Output is correct
40 Correct 248 ms 51956 KB Output is correct
41 Correct 111 ms 44408 KB Output is correct
42 Correct 129 ms 51700 KB Output is correct
43 Runtime error 196 ms 110188 KB Execution killed with signal 11 (could be triggered by violating memory limits)
44 Correct 184 ms 47352 KB Output is correct
45 Correct 175 ms 51704 KB Output is correct
46 Correct 184 ms 54640 KB Output is correct
47 Correct 186 ms 52232 KB Output is correct
48 Correct 171 ms 54884 KB Output is correct
49 Correct 72 ms 39928 KB Output is correct
50 Correct 155 ms 51316 KB Output is correct
51 Runtime error 227 ms 102132 KB Execution killed with signal 11 (could be triggered by violating memory limits)
52 Correct 143 ms 49144 KB Output is correct
53 Correct 188 ms 51580 KB Output is correct
54 Correct 256 ms 52592 KB Output is correct