Submission #59160

# Submission time Handle Problem Language Result Execution time Memory
59160 2018-07-20T21:15:34 Z Benq Pipes (BOI13_pipes) C++14
90.9259 / 100
380 ms 19420 KB
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;

ll N,M,in[MX],c[MX],ans[MX];
bool done[MX];
vpi adj[MX];

template<int SZ> struct DSU {
    int par[SZ], sz[SZ], val[SZ];
    DSU() {
        F0R(i,SZ) par[i] = i, sz[i] = 1;
    }
    
    int get(int x) { // path compression
    	if (par[x] != x) par[x] = get(par[x]);
    	return par[x];
    }
    
    bool unite(int x, int y) { // union-by-rank
    	x = get(x), y = get(y);
    	if (x == y) {
    	    val[x] ++;
    	    return 0;
    	}
    	if (sz[x] < sz[y]) swap(x,y);
    	sz[x] += sz[y], val[x] += val[y], par[y] = x;
    	return 1;
    }
};

DSU<MX> D;

vpi v;

void genCyc(int pre, int cur) {
    done[cur] = 1;
    for (auto a: adj[cur]) if (a.f != pre && !done[a.f]) {
        v.pb(a);
        genCyc(cur,a.f);
    }
}

ll cum[2*MX];

void solveCyc(int x) {
    v.clear(); 
    int pre = -1;
    for (auto y: adj[x]) if (!done[y.f]) {
        v.pb({x,y.s});
        pre = y.f;
        break;
    }
    genCyc(pre,x);
    if (sz(v) % 2 == 0) {
        cout << 0;
        exit(0);
    }
    ll sum = 0;
    for (auto a: v) sum += c[a.f];
    sum /= 2;
    
    F0R(i,2*sz(v)) {
        cum[i] = c[v[2*i%sz(v)].f];
        if (i) cum[i] += cum[i-1];
    }
    
    // v[1].s: {v[0].f,v[1].f}
    // v[3].s: {v[2].f,v[3].f}
    // 0: sum-(2+4+6+...+(N-1))
    F0R(i,sz(v)) {
        ans[v[i].s] = sum;
        int x = i+1; if (x&1) x += sz(v);
        // i+1, i+3, ..., i+N-2
        ans[v[i].s] += cum[x/2-1];
        ans[v[i].s] -= cum[(x+sz(v)-3)/2];
        // cout << "AH " << x << " " << sum << " " << cum[x/2-1] << " " << cum[(x+N-3)/2] << " " << ans[v[i].s] << "\n";
    }
    
    // cout << sz(v);
    // for (auto a: v) cout << a.f << " " << a.s << "\n";
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N >> M;
    FOR(i,1,N+1) cin >> c[i];
    FOR(i,1,M+1) {
        int a,b; cin >> a >> b;
        adj[a].pb({b,i}), adj[b].pb({a,i});
        D.unite(a,b);
        in[a] ++, in[b] ++;
    }
    FOR(i,1,N+1) if (D.val[D.get(i)] > D.sz[D.get(i)]) {
        cout << 0;
        exit(0);
    }
    queue<int> q;
    FOR(i,1,N+1) if (in[i] == 1) q.push(i);
    while (sz(q)) {
        int x = q.front(); q.pop(); done[x] = 1;
        if (in[x] == 0) {
            // cout << x << "\n";
            continue;
        }
        for (auto a: adj[x]) if (!done[a.f]) {
            ans[a.s] = c[x];
            c[a.f] -= ans[a.s];
            in[a.f] --;
            if (in[a.f] == 1) q.push(a.f);
        }
    }
    FOR(i,1,N+1) if (!done[i]) {
        if (in[i] == 0) {
            done[i] = 1;
        } else solveCyc(i);
    }
    FOR(i,1,M+1) cout << 2*ans[i] << "\n";
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/
# Verdict Execution time Memory Grader output
1 Correct 5 ms 3448 KB Output is correct
2 Correct 6 ms 3560 KB Output is correct
3 Correct 6 ms 3740 KB Output is correct
4 Correct 105 ms 10908 KB Output is correct
5 Correct 6 ms 10908 KB Output is correct
6 Correct 6 ms 10908 KB Output is correct
7 Correct 5 ms 10908 KB Output is correct
8 Correct 5 ms 10908 KB Output is correct
9 Correct 5 ms 10908 KB Output is correct
10 Correct 7 ms 10908 KB Output is correct
11 Correct 6 ms 10908 KB Output is correct
12 Correct 6 ms 10908 KB Output is correct
13 Correct 81 ms 10908 KB Output is correct
14 Correct 91 ms 10908 KB Output is correct
15 Correct 118 ms 10908 KB Output is correct
16 Correct 98 ms 10908 KB Output is correct
17 Correct 107 ms 10908 KB Output is correct
18 Correct 119 ms 11020 KB Output is correct
19 Correct 165 ms 11020 KB Output is correct
20 Correct 5 ms 11020 KB Output is correct
21 Correct 6 ms 11020 KB Output is correct
22 Correct 116 ms 11024 KB Output is correct
23 Correct 101 ms 11024 KB Output is correct
24 Correct 119 ms 11032 KB Output is correct
25 Correct 144 ms 11032 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 11032 KB Output is correct
2 Correct 6 ms 11032 KB Output is correct
3 Correct 95 ms 13112 KB Output is correct
4 Incorrect 157 ms 14788 KB Output isn't correct
5 Correct 118 ms 14788 KB Output is correct
6 Correct 380 ms 19420 KB Output is correct
7 Correct 5 ms 19420 KB Output is correct
8 Correct 6 ms 19420 KB Output is correct
9 Correct 5 ms 19420 KB Output is correct
10 Correct 6 ms 19420 KB Output is correct
11 Incorrect 6 ms 19420 KB Output isn't correct
12 Correct 6 ms 19420 KB Output is correct
13 Correct 6 ms 19420 KB Output is correct
14 Correct 7 ms 19420 KB Output is correct
15 Correct 6 ms 19420 KB Output is correct
16 Correct 6 ms 19420 KB Output is correct
17 Correct 6 ms 19420 KB Output is correct
18 Correct 8 ms 19420 KB Output is correct
19 Incorrect 8 ms 19420 KB Output isn't correct
20 Correct 8 ms 19420 KB Output is correct
21 Correct 8 ms 19420 KB Output is correct
22 Correct 8 ms 19420 KB Output is correct
23 Correct 121 ms 19420 KB Output is correct
24 Correct 145 ms 19420 KB Output is correct
25 Correct 121 ms 19420 KB Output is correct
26 Correct 136 ms 19420 KB Output is correct
27 Incorrect 147 ms 19420 KB Output isn't correct
28 Correct 123 ms 19420 KB Output is correct
29 Correct 350 ms 19420 KB Output is correct
30 Correct 125 ms 19420 KB Output is correct
31 Correct 117 ms 19420 KB Output is correct
32 Correct 147 ms 19420 KB Output is correct
33 Correct 136 ms 19420 KB Output is correct
34 Correct 131 ms 19420 KB Output is correct
35 Incorrect 137 ms 19420 KB Output isn't correct
36 Correct 116 ms 19420 KB Output is correct
37 Correct 362 ms 19420 KB Output is correct
38 Correct 198 ms 19420 KB Output is correct
39 Correct 134 ms 19420 KB Output is correct
40 Correct 137 ms 19420 KB Output is correct
41 Correct 130 ms 19420 KB Output is correct
42 Correct 137 ms 19420 KB Output is correct
43 Incorrect 120 ms 19420 KB Output isn't correct
44 Correct 83 ms 19420 KB Output is correct
45 Correct 333 ms 19420 KB Output is correct
46 Correct 138 ms 19420 KB Output is correct
47 Correct 142 ms 19420 KB Output is correct
48 Correct 143 ms 19420 KB Output is correct
49 Correct 103 ms 19420 KB Output is correct
50 Correct 119 ms 19420 KB Output is correct
51 Incorrect 163 ms 19420 KB Output isn't correct
52 Correct 124 ms 19420 KB Output is correct
53 Correct 328 ms 19420 KB Output is correct
54 Correct 182 ms 19420 KB Output is correct