oj.uz

Submission #84494

# Submission time Handle Problem Language Result Execution time Memory
84494 2018-11-15T16:10:24 Z Flying_dragon_02 Pipes (BOI13_pipes) C++14
100 / 100
 315 ms 30136 KB 
#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define pb push_back
#define mp make_pair

typedef pair<int, int> ii;

const int N = 1e5 + 5;

int n, m, c[N], deg[N], a[N], b[N];
long long x[N];

ii par[N];

vector<ii> graph[N];

bool vis[N], in[N];

vector<int> cycle;

void dfs(int u, int p, int type) {
    vis[u] = 1;
    for(int i = 0; i < graph[u].size(); i++) {
        int v = graph[u][i].fi;
        if(v == p) continue;
        if(vis[v] && type == 0 && in[v] == 0) {
            int z = u;
            while(z != v) {
                if(z == 0) break;
                cycle.pb(z);
                in[z] = 1;
                z = par[z].fi;
            }
            in[v] = 1;
            cycle.pb(v);
            continue;
        }
        if(vis[v]) continue;
        par[v] = {u, graph[u][i].se};
        dfs(v, u, type);
    }
    if(type == 1) {
        if(in[u] == 0) {
            ii lmao = par[u];
            x[lmao.se] = 2 * c[u];
            c[lmao.fi] = c[lmao.fi] - c[u];
            c[u] = 0;
        }
    }
}

void bfs(int u, int p) {
    for(int i = 0; i < graph[u].size(); i++) {
        int v = graph[u][i].fi;
        if(v == p) continue;
        bfs(v, u);
    }
    if(u != 1) {
        ii lmao = par[u];
        x[lmao.se] = 2 * c[u];
        c[lmao.fi] = c[lmao.fi] - c[u];
        c[u] = 0;
    }
}

void bye() {
    cout << "0\n";
    exit(0);
}

map<ii, int> edge;

queue<int> q;

int main() {
    cin.tie(0), ios::sync_with_stdio(0);
    cin >> n >> m;
    for(int i = 1; i <= n; i++)
        cin >> c[i];
    if(n < m)
        bye();
    for(int i = 1; i <= m; i++) {
        cin >> a[i] >> b[i];
        edge[{a[i], b[i]}] = i;
        edge[{b[i], a[i]}] = i;
        ++deg[a[i]]; ++deg[b[i]];
        graph[a[i]].pb({b[i], i});
        graph[b[i]].pb({a[i], i});
    }
    dfs(1, 1, 0);
    memset(vis, 0, sizeof(vis));
    if(n == m + 1) {
        bfs(1, 1);
        if(c[1] != 0)
            bye();
        for(int i = 1; i <= m; i++)
            cout << x[i] << "\n";
        exit(0);
    }
    if(cycle.size() % 2 == 0)
        bye();
    dfs(cycle[0], cycle[0], 1);
    long long total = 0, s = cycle.size() - 1;
    for(int i = 0; i < cycle.size(); i++) {
        if(i % 2 == 0)
            total += c[cycle[i]];
        else
            total -= c[cycle[i]];
    }
    x[edge[{cycle[0], cycle[s]}]] = total;
    if(total % 2 != 0)
        bye();
    c[cycle[0]] -= total / 2;
    c[cycle[s]] -= total / 2;
    for(int i = 0; i < cycle.size() - 1; i++) {
        x[edge[{cycle[i], cycle[i + 1]}]] = 2 * c[cycle[i]];
        c[cycle[i + 1]] = c[cycle[i + 1]] - c[cycle[i]];
        c[cycle[i]] = 0;
    }
    if(c[cycle[s]] != 0)
        bye();
    for(int i = 1; i <= m; i++) {
        if(x[i] > 1000000000 || x[i] < -1000000000)
            bye();
    }
    for(int i = 1; i <= n; i++) {
        if(c[i])
            bye();
    }
    for(int i = 1; i <= m; i++)
       cout << x[i] << "\n";
}

Compilation message

pipes.cpp: In function 'void dfs(int, int, int)':
pipes.cpp:27:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < graph[u].size(); i++) {
                    ~~^~~~~~~~~~~~~~~~~
pipes.cpp: In function 'void bfs(int, int)':
pipes.cpp:57:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < graph[u].size(); i++) {
                    ~~^~~~~~~~~~~~~~~~~
pipes.cpp: In function 'int main()':
pipes.cpp:108:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < cycle.size(); i++) {
                    ~~^~~~~~~~~~~~~~
pipes.cpp:119:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < cycle.size() - 1; i++) {
                    ~~^~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 2808 KB Output is correct
2 Correct 4 ms 2940 KB Output is correct
3 Correct 5 ms 3144 KB Output is correct
4 Correct 210 ms 22616 KB Output is correct
5 Correct 4 ms 22616 KB Output is correct
6 Correct 4 ms 22616 KB Output is correct
7 Correct 4 ms 22616 KB Output is correct
8 Correct 4 ms 22616 KB Output is correct
9 Correct 5 ms 22616 KB Output is correct
10 Correct 5 ms 22616 KB Output is correct
11 Correct 5 ms 22616 KB Output is correct
12 Correct 5 ms 22616 KB Output is correct
13 Correct 154 ms 22616 KB Output is correct
14 Correct 206 ms 22616 KB Output is correct
15 Correct 265 ms 22852 KB Output is correct
16 Correct 173 ms 22852 KB Output is correct
17 Correct 243 ms 22852 KB Output is correct
18 Correct 225 ms 22852 KB Output is correct
19 Correct 227 ms 26184 KB Output is correct
20 Correct 4 ms 26184 KB Output is correct
21 Correct 5 ms 26184 KB Output is correct
22 Correct 211 ms 26184 KB Output is correct
23 Correct 173 ms 26184 KB Output is correct
24 Correct 220 ms 26184 KB Output is correct
25 Correct 175 ms 26184 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 26184 KB Output is correct
2 Correct 5 ms 26184 KB Output is correct
3 Correct 195 ms 26184 KB Output is correct
4 Correct 13 ms 26184 KB Output is correct
5 Correct 13 ms 26184 KB Output is correct
6 Correct 14 ms 26184 KB Output is correct
7 Correct 4 ms 26184 KB Output is correct
8 Correct 4 ms 26184 KB Output is correct
9 Correct 4 ms 26184 KB Output is correct
10 Correct 4 ms 26184 KB Output is correct
11 Correct 4 ms 26184 KB Output is correct
12 Correct 4 ms 26184 KB Output is correct
13 Correct 4 ms 26184 KB Output is correct
14 Correct 4 ms 26184 KB Output is correct
15 Correct 5 ms 26184 KB Output is correct
16 Correct 5 ms 26184 KB Output is correct
17 Correct 5 ms 26184 KB Output is correct
18 Correct 4 ms 26184 KB Output is correct
19 Correct 4 ms 26184 KB Output is correct
20 Correct 4 ms 26184 KB Output is correct
21 Correct 4 ms 26184 KB Output is correct
22 Correct 5 ms 26184 KB Output is correct
23 Correct 224 ms 26184 KB Output is correct
24 Correct 264 ms 27156 KB Output is correct
25 Correct 202 ms 27156 KB Output is correct
26 Correct 14 ms 27156 KB Output is correct
27 Correct 13 ms 27156 KB Output is correct
28 Correct 13 ms 27156 KB Output is correct
29 Correct 14 ms 27156 KB Output is correct
30 Correct 286 ms 29648 KB Output is correct
31 Correct 315 ms 29780 KB Output is correct
32 Correct 253 ms 29780 KB Output is correct
33 Correct 210 ms 29780 KB Output is correct
34 Correct 13 ms 29780 KB Output is correct
35 Correct 13 ms 29780 KB Output is correct
36 Correct 14 ms 29780 KB Output is correct
37 Correct 14 ms 29780 KB Output is correct
38 Correct 276 ms 29780 KB Output is correct
39 Correct 238 ms 29780 KB Output is correct
40 Correct 263 ms 29780 KB Output is correct
41 Correct 212 ms 29780 KB Output is correct
42 Correct 14 ms 29780 KB Output is correct
43 Correct 14 ms 29780 KB Output is correct
44 Correct 13 ms 29780 KB Output is correct
45 Correct 9 ms 29780 KB Output is correct
46 Correct 274 ms 30136 KB Output is correct
47 Correct 292 ms 30136 KB Output is correct
48 Correct 294 ms 30136 KB Output is correct
49 Correct 180 ms 30136 KB Output is correct
50 Correct 14 ms 30136 KB Output is correct
51 Correct 13 ms 30136 KB Output is correct
52 Correct 13 ms 30136 KB Output is correct
53 Correct 11 ms 30136 KB Output is correct
54 Correct 277 ms 30136 KB Output is correct