Submission #253846

# Submission time Handle Problem Language Result Execution time Memory
253846 2020-07-28T22:11:19 Z aZvezda Pipes (BOI13_pipes) C++14
65 / 100
263 ms 24348 KB
#include <bits/stdc++.h>
using namespace std;
//#pragma GCC optimize ("O3")
//#pragma GCC target ("sse4")
#define endl "\n"
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
template<class T, class T2> inline bool chkmax(T &x, const T2 &y) { return x < y ? x = y, 1 : 0; }
template<class T, class T2> inline bool chkmin(T &x, const T2 &y) { return x > y ? x = y, 1 : 0; }
const ll mod = 1e9 + 7;
template<class T> inline void fix(T &x) {if(x >= mod | x <= -mod) {x %= mod;} if(x < 0) {x += mod;}}
#define out(x) cout << __LINE__ << ": " << (#x) << " = " << (x) << endl


//If we have an even cycle then we can add 1 on odd edges and -1 on even edges so the solutions stay the same. We can remove leaves one by one

const ll MAX_N = 1e5 + 10;
set<pair<ll, ll> > g[MAX_N];
ll ans[MAX_N], arr[MAX_N];

struct cmp {
    bool operator ()(const ll &a, const ll &b) const {
        if(g[a].size() == g[b].size()) {
            return a < b;
        }
        return g[a].size() < g[b].size();
    }
};

multiset<ll, cmp> pq;

void removeBranches() {
    while(!pq.empty() && g[*(pq.begin())].size() == 1) {
        ll curr = *(pq.begin()); pq.erase(pq.begin());
        auto other = *(g[curr].begin());
        pq.erase(other.first);
        ans[other.second] = 2 * arr[curr];
        arr[other.first] -= arr[curr];
        g[other.first].erase({curr, other.second});
        pq.insert(other.first);
    }
}

int rret = 0;

void dfs(int x, int p, int start, int flag) {
    rret += arr[x] * flag;
    //cout << x << " " << p << " " << ans[x] << " " << rret << endl;
    for(auto it : g[x]) {
        if(it.first == p || it.first == start) {continue;}
        dfs(it.first, x, start, -flag);
    }
}

void removeCycle() {
    return;
    if(pq.empty()) {return;}
    auto now = pq.begin();
    if(g[*now].size() > 2) {
        cout << 0 << endl;
        exit(0);
    }
    now = pq.end(); now --;
    if(g[*now].size() > 2) {
        cout << 0 << endl;
        exit(0);
    }
    if(pq.size() % 2 == 0) {
        cout << 0 << endl;
        exit(0);
    }
    int curr = *(pq.begin());
    dfs(curr, (*(g[curr].begin())).first, curr, 1);
    rret /= 2;
    auto sec = (g[curr].begin());
    arr[curr] -= rret;
    arr[(*sec).first] -= rret;
    ans[(*sec).second] = rret;
    g[curr].erase(sec);
    g[(*sec).first].erase({curr, (*sec).second});
    //cout << curr << " " << (*sec).first << " " << rret << endl;
}

signed main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
    ll n, m;
    cin >> n >> m;
    if(m > n) {cout << 0 << endl; return 0;}
    for(ll i = 1; i <= n; i ++) {
        cin >> arr[i];
    }
    for(ll i = 0; i < m; i ++) {
        ll a, b;
        cin >> a >> b;
        g[a].insert({b, i});
        g[b].insert({a, i});
    }
    for(ll i = 1; i <= n; i ++) {
        pq.insert(i);
    }
    removeBranches();
    removeCycle();
    removeBranches();
    for(ll i = 0; i < m; i ++) {
        cout << ans[i] << endl;
    }
    return 0;
}


# Verdict Execution time Memory Grader output
1 Correct 3 ms 4992 KB Output is correct
2 Correct 4 ms 4992 KB Output is correct
3 Correct 5 ms 5248 KB Output is correct
4 Correct 247 ms 24304 KB Output is correct
5 Correct 3 ms 4992 KB Output is correct
6 Correct 3 ms 4992 KB Output is correct
7 Correct 3 ms 4992 KB Output is correct
8 Correct 3 ms 4992 KB Output is correct
9 Correct 4 ms 5248 KB Output is correct
10 Correct 4 ms 5248 KB Output is correct
11 Correct 4 ms 5248 KB Output is correct
12 Correct 4 ms 5248 KB Output is correct
13 Correct 188 ms 20344 KB Output is correct
14 Correct 228 ms 23288 KB Output is correct
15 Correct 226 ms 24312 KB Output is correct
16 Correct 189 ms 21624 KB Output is correct
17 Correct 236 ms 24156 KB Output is correct
18 Correct 263 ms 24288 KB Output is correct
19 Correct 174 ms 24312 KB Output is correct
20 Correct 3 ms 4992 KB Output is correct
21 Correct 4 ms 5248 KB Output is correct
22 Correct 217 ms 24180 KB Output is correct
23 Correct 170 ms 20312 KB Output is correct
24 Correct 239 ms 24312 KB Output is correct
25 Correct 177 ms 20988 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 4 ms 4992 KB Output isn't correct
2 Incorrect 4 ms 5248 KB Output isn't correct
3 Incorrect 188 ms 23056 KB Output isn't correct
4 Correct 3 ms 4992 KB Output is correct
5 Correct 3 ms 4992 KB Output is correct
6 Correct 3 ms 4992 KB Output is correct
7 Incorrect 3 ms 4992 KB Output isn't correct
8 Incorrect 3 ms 4992 KB Output isn't correct
9 Incorrect 3 ms 4992 KB Output isn't correct
10 Correct 3 ms 4992 KB Output is correct
11 Correct 3 ms 4992 KB Output is correct
12 Correct 3 ms 4992 KB Output is correct
13 Correct 3 ms 4992 KB Output is correct
14 Incorrect 3 ms 4992 KB Output isn't correct
15 Incorrect 4 ms 5248 KB Output isn't correct
16 Incorrect 4 ms 5248 KB Output isn't correct
17 Incorrect 4 ms 5248 KB Output isn't correct
18 Correct 3 ms 4992 KB Output is correct
19 Correct 3 ms 4992 KB Output is correct
20 Correct 3 ms 4992 KB Output is correct
21 Correct 3 ms 4992 KB Output is correct
22 Incorrect 4 ms 5248 KB Output isn't correct
23 Incorrect 116 ms 20472 KB Output isn't correct
24 Incorrect 161 ms 24184 KB Output isn't correct
25 Incorrect 163 ms 23032 KB Output isn't correct
26 Correct 4 ms 4992 KB Output is correct
27 Correct 3 ms 4992 KB Output is correct
28 Correct 3 ms 4992 KB Output is correct
29 Correct 3 ms 4992 KB Output is correct
30 Incorrect 143 ms 23808 KB Output isn't correct
31 Incorrect 116 ms 24056 KB Output isn't correct
32 Incorrect 202 ms 24184 KB Output isn't correct
33 Incorrect 162 ms 24184 KB Output isn't correct
34 Correct 3 ms 4992 KB Output is correct
35 Correct 4 ms 4992 KB Output is correct
36 Correct 3 ms 4992 KB Output is correct
37 Correct 3 ms 4992 KB Output is correct
38 Incorrect 150 ms 24128 KB Output isn't correct
39 Incorrect 208 ms 24184 KB Output isn't correct
40 Incorrect 165 ms 24184 KB Output isn't correct
41 Incorrect 114 ms 24056 KB Output isn't correct
42 Correct 3 ms 4992 KB Output is correct
43 Correct 3 ms 4992 KB Output is correct
44 Correct 3 ms 4992 KB Output is correct
45 Correct 3 ms 4992 KB Output is correct
46 Incorrect 146 ms 24168 KB Output isn't correct
47 Incorrect 165 ms 24348 KB Output isn't correct
48 Incorrect 116 ms 24060 KB Output isn't correct
49 Incorrect 195 ms 23032 KB Output isn't correct
50 Correct 3 ms 4992 KB Output is correct
51 Correct 3 ms 4992 KB Output is correct
52 Correct 3 ms 4992 KB Output is correct
53 Correct 3 ms 4992 KB Output is correct
54 Incorrect 159 ms 23912 KB Output isn't correct