Submission #251602

# Submission time Handle Problem Language Result Execution time Memory
251602 2020-07-22T02:46:56 Z abacaba Pipes (BOI13_pipes) C++14
48.1481 / 100
418 ms 68856 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 ans[N];

vector <int> comp[N];

set <int> cycles;
vector <int> inc;

int pp[N];

int pref[2][N];

vector <int> G[N];

bool tw[N];
bool used2[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]);
}

int calc(int i, int sum) {
    int v = now[i];
    int ind = -1;
    int val;
    if(i + 1 < now.size()) {
        for(int j = 0; j < g[v].size(); ++j)
            if(gt(g[v][j], v) == now[i + 1])
                ind = g[v][j];
        assert(ind != -1);
        val = get(i + 2, i + 2, now.size() - 1) + get(i - 1, 0, i - 1);
    }
    else {
        for(int j = 0; j < g[v].size(); ++j)
            if(gt(g[v][j], v) == now[0])
                ind = g[v][j];
        assert(ind != -1);
        val = get(1, 1, now.size() - 2);
    }
    return ans[ind] = sum - 2 * val;
}

void solve_for_cycle(int s) {
    if(sz[s] == 1) {
        for(int ind : G[s]) {
            int x = e[ind].f, y = e[ind].se;
            if(find(y) == s)
                swap(x, y);
            int to = find(y);
            if(used2[to])
                continue;
            ans[ind] = 2 * a[x];
            cur.erase({deg[to], to});
            --deg[to];
            cur.insert({deg[to], to});
        }
        return;
    }
    int sum = 0;
    for(int v : now)
        sum += a[v];
    now.clear();
    dfs(comp[s][0]);
    int start = 0;
    int x, y;
    for(int ind : G[s]) {
        x = e[ind].f, y = e[ind].se;
        if(find(y) == s)
            swap(x, y);
        int to = find(y);
        if(!used2[to])
            break;
    }
    for(int i = 0; i < now.size(); ++i) {
        if(now[i] == x) {
            start = i;
            break;
        }
    }
    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]];
    }
    int prev = calc(start, sum);
    for(int i = start + 1; i < 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) % now.size()])
                ind = g[v][j];
        ans[ind] = 2 * a[v] - prev;
        prev = ans[ind];
    }
    for(int i = 0; i < start; ++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) % now.size()])
                ind = g[v][j];
        ans[ind] = 2 * a[v] - prev;
        prev = ans[ind];
    }
    int sum_of_start_in_cycle = 0;
    int v = now[start];
    for(int ind : g[v]) {
        int to = gt(ind, v);
        if(find(to) == s)
            sum_of_start_in_cycle += ans[ind];
    }
    for(int ind : g[v]) {
        int to = gt(ind, v);
        // cout << find(to) << ' ' << ans[ind] << endl;
    }
    for(int ind : g[v]) {
        int x = v, y = gt(ind, v);
        if(find(y) == s)
            swap(x, y);
        int to = find(y);
        if(!used2[to]) {
            ans[ind] = 2 * a[v] - sum_of_start_in_cycle;
            // cout << a[v] << ' ' << ind << ' ' << sum_of_start_in_cycle << endl;
        }
    }
}

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 v = 1; v <= n; ++v) {
        for(int ind : g[v]) {
            int to = gt(ind, v);
            if(find(v) != find(to))
                G[find(v)].pb(ind);
        }
    }
    memset(used, 0, sizeof(used));
    for(int i = 1; i <= n; ++i) {
        comp[find(i)].pb(i);
        deg[find(i)] = G[find(i)].size();
        cur.insert({deg[find(i)], find(i)});
    }
    while(!cur.empty()) {
        int v = cur.begin()->se;
        cur.erase(cur.begin());

        used2[v] = true;
        for(int ind : G[v]) {
            int x = e[ind].f, y = e[ind].se;
            if(find(y) == v)
                swap(x, y);
            int to = find(y);
            if(used2[to])
                a[x] -= ans[ind] / 2;
        }
        solve_for_cycle(v);
    }
    for(int i = 1; i <= n; ++i) {
        int val = 0;
        for(int ind : g[i])
            val += ans[ind] / 2;
        // cout << "asdsa: " << val << endl;
    }
    for(int i = 1; i <= m; ++i)
        cout << ans[i] << endl;
    return 0;
}

Compilation message

pipes.cpp: In function 'long long int calc(long long int, long long int)':
pipes.cpp:164:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if(i + 1 < now.size()) {
        ~~~~~~^~~~~~~~~~~~
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:172:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[v].size(); ++j)
                        ~~^~~~~~~~~~~~~
pipes.cpp: In function 'void solve_for_cycle(long long int)':
pipes.cpp:212:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < now.size(); ++i) {
                    ~~^~~~~~~~~~~~
pipes.cpp:218:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < now.size(); ++i) {
                    ~~^~~~~~~~~~~~
pipes.cpp:224:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = start + 1; i < now.size(); ++i) {
                            ~~^~~~~~~~~~~~
pipes.cpp:227:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[v].size(); ++j)
                        ~~^~~~~~~~~~~~~
pipes.cpp:236:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j = 0; j < g[v].size(); ++j)
                        ~~^~~~~~~~~~~~~
pipes.cpp:250:13: warning: unused variable 'to' [-Wunused-variable]
         int to = gt(ind, v);
             ^~
pipes.cpp: At global scope:
pipes.cpp:265:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
pipes.cpp: In function 'void solve_for_cycle(long long int)':
pipes.cpp:213:9: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
         if(now[i] == x) {
         ^~
# Verdict Execution time Memory Grader output
1 Correct 24 ms 44032 KB Output is correct
2 Correct 28 ms 44032 KB Output is correct
3 Correct 25 ms 44160 KB Output is correct
4 Correct 249 ms 66808 KB Output is correct
5 Correct 26 ms 43904 KB Output is correct
6 Correct 24 ms 43904 KB Output is correct
7 Correct 26 ms 44024 KB Output is correct
8 Correct 24 ms 44024 KB Output is correct
9 Correct 26 ms 44160 KB Output is correct
10 Correct 25 ms 44160 KB Output is correct
11 Correct 26 ms 44160 KB Output is correct
12 Correct 25 ms 44288 KB Output is correct
13 Correct 219 ms 62304 KB Output is correct
14 Correct 248 ms 65496 KB Output is correct
15 Correct 264 ms 66808 KB Output is correct
16 Correct 254 ms 63392 KB Output is correct
17 Correct 250 ms 66808 KB Output is correct
18 Correct 330 ms 66808 KB Output is correct
19 Correct 319 ms 68856 KB Output is correct
20 Correct 24 ms 44028 KB Output is correct
21 Correct 25 ms 44160 KB Output is correct
22 Correct 418 ms 66936 KB Output is correct
23 Correct 188 ms 62072 KB Output is correct
24 Correct 267 ms 66948 KB Output is correct
25 Correct 208 ms 62968 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 28 ms 44032 KB Output isn't correct
2 Incorrect 28 ms 44160 KB Output isn't correct
3 Correct 112 ms 53368 KB Output is correct
4 Incorrect 213 ms 63716 KB Output isn't correct
5 Incorrect 267 ms 65144 KB Output isn't correct
6 Correct 235 ms 66552 KB Output is correct
7 Incorrect 24 ms 44024 KB Output isn't correct
8 Incorrect 25 ms 44032 KB Output isn't correct
9 Correct 25 ms 43520 KB Output is correct
10 Incorrect 24 ms 44024 KB Output isn't correct
11 Incorrect 28 ms 44032 KB Output isn't correct
12 Incorrect 24 ms 44032 KB Output isn't correct
13 Correct 24 ms 43512 KB Output is correct
14 Incorrect 24 ms 44032 KB Output isn't correct
15 Incorrect 25 ms 44152 KB Output isn't correct
16 Incorrect 25 ms 44160 KB Output isn't correct
17 Correct 24 ms 43520 KB Output is correct
18 Incorrect 26 ms 44160 KB Output isn't correct
19 Incorrect 31 ms 44152 KB Output isn't correct
20 Incorrect 32 ms 44160 KB Output isn't correct
21 Correct 24 ms 43648 KB Output is correct
22 Incorrect 29 ms 44156 KB Output isn't correct
23 Incorrect 153 ms 60656 KB Output isn't correct
24 Incorrect 246 ms 64876 KB Output isn't correct
25 Correct 99 ms 53368 KB Output is correct
26 Incorrect 231 ms 64240 KB Output isn't correct
27 Incorrect 197 ms 62108 KB Output isn't correct
28 Incorrect 285 ms 63224 KB Output isn't correct
29 Correct 245 ms 62072 KB Output is correct
30 Incorrect 200 ms 66796 KB Output isn't correct
31 Incorrect 186 ms 63468 KB Output isn't correct
32 Incorrect 327 ms 66416 KB Output isn't correct
33 Correct 104 ms 54264 KB Output is correct
34 Incorrect 309 ms 67576 KB Output isn't correct
35 Incorrect 188 ms 63716 KB Output isn't correct
36 Incorrect 234 ms 63996 KB Output isn't correct
37 Correct 239 ms 66552 KB Output is correct
38 Incorrect 207 ms 66416 KB Output isn't correct
39 Incorrect 255 ms 66424 KB Output isn't correct
40 Incorrect 208 ms 65124 KB Output isn't correct
41 Correct 93 ms 56184 KB Output is correct
42 Incorrect 176 ms 61676 KB Output isn't correct
43 Incorrect 167 ms 62180 KB Output isn't correct
44 Incorrect 341 ms 65016 KB Output isn't correct
45 Correct 186 ms 63224 KB Output is correct
46 Incorrect 267 ms 68076 KB Output isn't correct
47 Incorrect 285 ms 64876 KB Output isn't correct
48 Incorrect 210 ms 63468 KB Output isn't correct
49 Correct 83 ms 51576 KB Output is correct
50 Incorrect 271 ms 64880 KB Output isn't correct
51 Incorrect 208 ms 63980 KB Output isn't correct
52 Incorrect 175 ms 58744 KB Output isn't correct
53 Correct 223 ms 63288 KB Output is correct
54 Incorrect 210 ms 66672 KB Output isn't correct