Submission #240495

#	Time	Username	Problem	Language	Result	Execution time	Memory
240495		karma	Senior Postmen (BOI14_postmen)	C++14	100 / 100	487 ms	44792 KiB

postmen

#include <bits/stdc++.h>

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,avx2,fma")

#define pb          emplace_back
#define ll          long long
#define fi          first
#define se          second
#define mp          make_pair
//#define int         int64_t

using namespace std;

const int N = int(5e5) + 10;
typedef pair<int, int> pii;

struct TEdge {
    int u, v;
    bool del;
} e[N];
int n, m, vis[N], ss[N], st[N], cnts, cntt;
int path[N], cp, u, id;
vector<vector<int>> adj;

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    #define Task        "test"
    if(fopen(Task".inp", "r")) {
        freopen(Task".inp", "r", stdin);
        freopen(Task".out", "w", stdout);
    }
    cin >> n >> m; adj.resize(n + 1);
    for(int i = 1; i <= m; ++i) {
        cin >> e[i].u >> e[i].v;
        adj[e[i].u].pb(i);
        adj[e[i].v].pb(i);
    }
    path[++cp] = 1;
    do {
        u = path[cp];
        while(adj[u].size() && e[adj[u].back()].del) adj[u].pop_back();
        if(adj[u].size()) {
            id = adj[u].back();
            adj[u].pop_back();
            e[id].del = 1;
            path[++cp] = e[id].u ^ e[id].v ^ u;
        } else {
            st[++cntt] = u;
            --cp;
        }
    } while(cp > 0);
    while(cntt) {
        u = st[cntt];
        if(vis[u]) {
            while(1) {
                vis[ss[cnts]] = 0;
                cout << ss[cnts] << ' ';
                if(ss[cnts --] == u) break;
            }
            cout << '\n';
        }
        vis[u] = 1;
        ss[++cnts] = u;
        --cntt;
    }
}

Compilation message (stderr)

postmen.cpp: In function 'int32_t main()':
postmen.cpp:31:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".inp", "r", stdin);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
postmen.cpp:32:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".out", "w", stdout);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 38 / 38
• Subtask 2: 17 / 17
• Subtask 3: 45 / 45