답안 #88717 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
88717	2018-12-07T18:43:19 Z	popovicirobert	Pipes (BOI13_pipes)	C++14	100 / 100	288 ms	22548 KB

pipes

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44

using namespace std;

const int MAXM = (int) 5e5;
const int MAXN = (int) 1e5;

vector < pair <int, int> > g[MAXN + 1];
int even[MAXN + 1], father[MAXN + 1], n;
bool vis[MAXN + 1];

void dfs(int nod) {
    vis[nod] = 1;
    for(auto it : g[nod]) {
        if(vis[it.first] == 0) {
            even[it.first] = (even[nod] ^ 1);
            father[it.first] = nod;
            dfs(it.first);
        }
    }
}

inline void detect_cycle(bool &cycle) {
    memset(even, -1, sizeof(even));
    even[1] = 0;
    dfs(1);
    int cnt = 0;
    for(int i = 1; i <= n; i++) {
        for(auto it : g[i]) {
            if(even[i] != even[it.first] && !(father[it.first] == i || father[i] == it.first)) {
                cout << 0;
                exit(0);
            }
            if(even[i] == even[it.first]) {
                cnt++;
            }
        }
    }
    cnt /= 2;
    if(cnt > 1) {
        cout << 0;
        exit(0);
    }
    if(cnt) {
        cycle = 1;
    }
}

ll c[MAXN + 1];
ll sol[MAXM + 1];

int deg[MAXN + 1];

inline void solve_tree(bool cycle) {
    int i;
    memset(father, 0, sizeof(father));
    memset(vis, 0, sizeof(vis));
    queue <int> Q;
    for(i = 1; i <= n; i++) {
        if(g[i].size() == 1) {
            Q.push(i);
            vis[i] = 1;
        }
    }
    int root;
    while(Q.size()) {
        int nod = Q.front();
        root = nod;
        Q.pop();
        for(auto it : g[nod]) {
            if(father[it.first] != nod) {
                deg[it.first]++;
                father[nod] = it.first;
                sol[it.second] = c[nod];
                c[it.first] -= c[nod];
                c[nod] = 0;
                if(deg[it.first] + 1 == g[it.first].size()) {
                    Q.push(it.first);
                    vis[it.first] = 1;
                }
            }
        }
    }
    if(cycle == 0) {
        for(i = 1; i <= n; i++) {
            if(c[i] != 0) {
                cout << 0;
                exit(0);
            }
        }
    }
}

void dfs1(int nod, vector < pair <int, int> > &nodes, int par, int root) {
    vis[nod] = 1;
    for(auto it : g[nod]) {
        if(it.first == par) {
            continue;
        }
        if(vis[it.first] == 0) {
            nodes.push_back({nod, it.second});
            dfs1(it.first, nodes, nod, root);
        }
        else if(it.first == root) {
            nodes.push_back({nod, it.second});
        }
    }
}

inline void solve_cycle(bool cycle) {
    if(cycle == 0) {
        return ;
    }
    int i, nod;
    for(i = 1; i <= n; i++) {
        if(vis[i] == 0) {
            nod = i;
            break;
        }
    }
    vector < pair <int, int> > nodes;
    dfs1(nod, nodes, 0, nod);
    int sz = nodes.size();
    ll tot = 0;
    for(auto it : nodes) {
        tot += c[it.first];
    }
    tot /= 2;
    ll sum = 0;
    for(i = 0; i + 1 < sz; i += 2) {
        sum += c[nodes[i].first];
    }
    sol[nodes[sz - 2].second] = tot - sum;
    c[nodes[sz - 2].first] -= tot - sum;
    for(i = sz - 3; i >= 0; i--) {
        sol[nodes[i].second] = c[nodes[i + 1].first];
        c[nodes[i].first] -= sol[nodes[i].second];
    }
    sum = 0;
    for(auto it : nodes) {
        sum += sol[it.second];
    }
    sol[nodes.back().second] = tot - sum;
}

int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int i, m;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);
    cin >> n >> m;
    for(i = 1; i <= n; i++) {
        cin >> c[i];
        c[i] *= 2LL;
    }
    for(i = 1; i <= m; i++) {
        int x, y;
        cin >> x >> y;
        g[x].push_back({y, i});
        g[y].push_back({x, i});
    }
    bool cycle = 0;
    detect_cycle(cycle);
    solve_tree(cycle);
    solve_cycle(cycle);
    for(i = 1; i <= m; i++) {
        cout << sol[i] << "\n";
    }
    //cin.close();
    //cout.close();
    return 0;
}

Compilation message

pipes.cpp: In function 'void solve_tree(bool)':
pipes.cpp:82:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if(deg[it.first] + 1 == g[it.first].size()) {
                    ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
pipes.cpp:70:9: warning: variable 'root' set but not used [-Wunused-but-set-variable]
     int root;
         ^~~~
pipes.cpp: In function 'void solve_cycle(bool)':
pipes.cpp:127:9: warning: 'nod' may be used uninitialized in this function [-Wmaybe-uninitialized]
     dfs1(nod, nodes, 0, nod);
     ~~~~^~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	3580 KB	Output is correct
2	Correct	4 ms	3708 KB	Output is correct
3	Correct	5 ms	3784 KB	Output is correct
4	Correct	93 ms	10108 KB	Output is correct
5	Correct	5 ms	10108 KB	Output is correct
6	Correct	4 ms	10108 KB	Output is correct
7	Correct	4 ms	10108 KB	Output is correct
8	Correct	5 ms	10108 KB	Output is correct
9	Correct	5 ms	10108 KB	Output is correct
10	Correct	5 ms	10108 KB	Output is correct
11	Correct	5 ms	10108 KB	Output is correct
12	Correct	5 ms	10108 KB	Output is correct
13	Correct	67 ms	10108 KB	Output is correct
14	Correct	80 ms	10108 KB	Output is correct
15	Correct	86 ms	10220 KB	Output is correct
16	Correct	76 ms	10220 KB	Output is correct
17	Correct	89 ms	10244 KB	Output is correct
18	Correct	90 ms	10244 KB	Output is correct
19	Correct	100 ms	11836 KB	Output is correct
20	Correct	5 ms	11836 KB	Output is correct
21	Correct	5 ms	11836 KB	Output is correct
22	Correct	85 ms	11836 KB	Output is correct
23	Correct	67 ms	11836 KB	Output is correct
24	Correct	97 ms	11836 KB	Output is correct
25	Correct	75 ms	11836 KB	Output is correct

Subtask #2
70.0 / 70.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	11836 KB	Output is correct
2	Correct	5 ms	11836 KB	Output is correct
3	Correct	73 ms	11836 KB	Output is correct
4	Correct	80 ms	11836 KB	Output is correct
5	Correct	72 ms	11836 KB	Output is correct
6	Correct	279 ms	22372 KB	Output is correct
7	Correct	4 ms	22372 KB	Output is correct
8	Correct	4 ms	22372 KB	Output is correct
9	Correct	4 ms	22372 KB	Output is correct
10	Correct	4 ms	22372 KB	Output is correct
11	Correct	4 ms	22372 KB	Output is correct
12	Correct	4 ms	22372 KB	Output is correct
13	Correct	5 ms	22372 KB	Output is correct
14	Correct	4 ms	22372 KB	Output is correct
15	Correct	5 ms	22372 KB	Output is correct
16	Correct	5 ms	22372 KB	Output is correct
17	Correct	4 ms	22372 KB	Output is correct
18	Correct	5 ms	22372 KB	Output is correct
19	Correct	4 ms	22372 KB	Output is correct
20	Correct	5 ms	22372 KB	Output is correct
21	Correct	5 ms	22372 KB	Output is correct
22	Correct	5 ms	22372 KB	Output is correct
23	Correct	82 ms	22372 KB	Output is correct
24	Correct	117 ms	22372 KB	Output is correct
25	Correct	69 ms	22372 KB	Output is correct
26	Correct	77 ms	22372 KB	Output is correct
27	Correct	74 ms	22372 KB	Output is correct
28	Correct	75 ms	22372 KB	Output is correct
29	Correct	233 ms	22372 KB	Output is correct
30	Correct	101 ms	22372 KB	Output is correct
31	Correct	104 ms	22372 KB	Output is correct
32	Correct	92 ms	22372 KB	Output is correct
33	Correct	71 ms	22372 KB	Output is correct
34	Correct	73 ms	22372 KB	Output is correct
35	Correct	77 ms	22372 KB	Output is correct
36	Correct	68 ms	22372 KB	Output is correct
37	Correct	288 ms	22548 KB	Output is correct
38	Correct	113 ms	22548 KB	Output is correct
39	Correct	87 ms	22548 KB	Output is correct
40	Correct	100 ms	22548 KB	Output is correct
41	Correct	79 ms	22548 KB	Output is correct
42	Correct	74 ms	22548 KB	Output is correct
43	Correct	81 ms	22548 KB	Output is correct
44	Correct	68 ms	22548 KB	Output is correct
45	Correct	206 ms	22548 KB	Output is correct
46	Correct	106 ms	22548 KB	Output is correct
47	Correct	113 ms	22548 KB	Output is correct
48	Correct	101 ms	22548 KB	Output is correct
49	Correct	66 ms	22548 KB	Output is correct
50	Correct	80 ms	22548 KB	Output is correct
51	Correct	78 ms	22548 KB	Output is correct
52	Correct	79 ms	22548 KB	Output is correct
53	Correct	219 ms	22548 KB	Output is correct
54	Correct	105 ms	22548 KB	Output is correct

답안 #88717

Compilation message

Subtask #1 30.0 / 30.0

Subtask #2 70.0 / 70.0

Subtask #1
30.0 / 30.0

Subtask #2
70.0 / 70.0