Submission #59190

# Submission time Handle Problem Language Result Execution time Memory
59190 2018-07-21T01:22:25 Z Benq 007 (CEOI14_007) C++14
100 / 100
509 ms 19768 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 = 200001;

int n,m,s,d,a,b,split[MX];
vi adj[MX];
int dist[2][MX];

void genDist(int k) {
    queue<int> q;
    FOR(i,1,n+1) dist[k][i] = MOD;
    if (k == 0) {
        dist[k][a] = 0; q.push(a);
    } else {
        dist[k][b] = 0; q.push(b);
    }
    while (sz(q)) {
        int x = q.front(); q.pop();
        for (int i: adj[x]) if (dist[k][i] == MOD) {
            dist[k][i] = dist[k][x]+1;
            q.push(i);
        }
    }
}

void genSplit() {
    vector<array<int,3>> v;
    FOR(i,1,n+1) v.pb({dist[0][i],dist[1][i],i});
    sort(all(v));
    for (auto a: v) if (a[0] == a[1]) {
        split[a[2]] = a[0];
        for (auto x: adj[a[2]]) 
            if (dist[0][x] == dist[1][x] && dist[0][x] < a[0])
                split[a[2]] = min(split[a[2]],split[x]);
    }
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> m;
    cin >> s >> d >> a >> b;
    F0R(i,m) {
        int x,y; cin >> x >> y;
        adj[x].pb(y), adj[y].pb(x);
    }
    genDist(0), genDist(1);
    genSplit();
    int ans = min(dist[0][d]-dist[0][s],dist[1][d]-dist[1][s]);
    if (dist[0][d] == dist[1][d] && dist[0][s] == dist[1][s]) 
        if (split[d] < split[s]) ans --;
    
    cout << max(ans,-1);
    // if equally close to one server, who wins?
    // if equally close to both servers, who wins?
}

/* 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 6 ms 4984 KB Output is correct
2 Correct 8 ms 5092 KB Output is correct
3 Correct 6 ms 5168 KB Output is correct
4 Correct 6 ms 5200 KB Output is correct
5 Correct 6 ms 5200 KB Output is correct
6 Correct 6 ms 5220 KB Output is correct
7 Correct 6 ms 5220 KB Output is correct
8 Correct 6 ms 5220 KB Output is correct
9 Correct 6 ms 5276 KB Output is correct
10 Correct 6 ms 5352 KB Output is correct
11 Correct 7 ms 5352 KB Output is correct
12 Correct 8 ms 5372 KB Output is correct
13 Correct 6 ms 5372 KB Output is correct
14 Correct 6 ms 5372 KB Output is correct
15 Correct 7 ms 5372 KB Output is correct
16 Correct 6 ms 5372 KB Output is correct
17 Correct 7 ms 5372 KB Output is correct
18 Correct 8 ms 5372 KB Output is correct
19 Correct 7 ms 5372 KB Output is correct
20 Correct 8 ms 5372 KB Output is correct
21 Correct 9 ms 5372 KB Output is correct
22 Correct 7 ms 5372 KB Output is correct
23 Correct 8 ms 5372 KB Output is correct
24 Correct 8 ms 5372 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 47 ms 7944 KB Output is correct
2 Correct 64 ms 8724 KB Output is correct
3 Correct 49 ms 8724 KB Output is correct
4 Correct 68 ms 8820 KB Output is correct
5 Correct 46 ms 8820 KB Output is correct
6 Correct 47 ms 8820 KB Output is correct
7 Correct 51 ms 8820 KB Output is correct
8 Correct 57 ms 8820 KB Output is correct
9 Correct 71 ms 8820 KB Output is correct
10 Correct 246 ms 13044 KB Output is correct
11 Correct 99 ms 13044 KB Output is correct
12 Correct 136 ms 13044 KB Output is correct
13 Correct 103 ms 13044 KB Output is correct
14 Correct 103 ms 13044 KB Output is correct
15 Correct 128 ms 13044 KB Output is correct
16 Correct 134 ms 13044 KB Output is correct
17 Correct 121 ms 13044 KB Output is correct
18 Correct 132 ms 13044 KB Output is correct
19 Correct 200 ms 13044 KB Output is correct
20 Correct 340 ms 15468 KB Output is correct
21 Correct 185 ms 15468 KB Output is correct
22 Correct 152 ms 15468 KB Output is correct
23 Correct 177 ms 15468 KB Output is correct
24 Correct 145 ms 15468 KB Output is correct
25 Correct 170 ms 15468 KB Output is correct
26 Correct 170 ms 15468 KB Output is correct
27 Correct 185 ms 15468 KB Output is correct
28 Correct 205 ms 15468 KB Output is correct
29 Correct 277 ms 15484 KB Output is correct
30 Correct 403 ms 16660 KB Output is correct
31 Correct 231 ms 16660 KB Output is correct
32 Correct 162 ms 16660 KB Output is correct
33 Correct 171 ms 16660 KB Output is correct
34 Correct 184 ms 16660 KB Output is correct
35 Correct 149 ms 16660 KB Output is correct
36 Correct 157 ms 16660 KB Output is correct
37 Correct 227 ms 16660 KB Output is correct
38 Correct 261 ms 16660 KB Output is correct
39 Correct 274 ms 16660 KB Output is correct
40 Correct 341 ms 17648 KB Output is correct
41 Correct 509 ms 19768 KB Output is correct