Submission #31397

#	Time	Username	Problem	Language	Result	Execution time	Memory
31397		imaxblue	Senior Postmen (BOI14_postmen)	C++14	0 / 100	15 ms	12160 KiB

postmen

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define mp make_pair
#define pb push_back
#define x first
#define y second
#define pii pair<int, int>
#define p3i pair<pii, int>
#define pll pair<ll, ll>
#define p3l pair<pll, ll>
#define lseg L, (L+R)/2, N*2+1
#define rseg (L+R)/2+1, R, N*2+2
#define ub upper_bound
#define lb lower_bound
#define pq priority_queue
#define MN 1000000007
#define fox(k, x) for (int k=0; k<x; ++k)
#define fox1(k, x) for (int k=1; k<=x; ++k)
#define foxr(k, x) for (int k=x-1; k>=0; --k)
#define fox1r(k, x) for (int k=x; k>0; --k)
#define ms multiset
#define flood(x) memset(x, 0x3f3f3f3f, sizeof x)
#define drain(x) memset(x, 0, sizeof x)
#define rng() (rand() >> 3)*rand()

int n, m, a, b, t, p[500005];
bool u[500005], u2[500005];
vector<pii> v[500005];
vector<int> s, ans;
set<int> S;
void dfs(int N){
    if (u[N]){
        t=-1;
        ans.clear();
        while(t!=N){
            //ans.pb(e.back()); e.pop_back();
            ans.pb(t=s.back()); s.pop_back();
            u[t]=0;
        }
        S.clear();
        reverse(ans.begin(), ans.end());
        fox(l, ans.size()){
            cout << ans[l] << ' ';
            if (S.find(ans[l])!=S.end()) exit(1);
            S.insert(ans[l]);
        }cout << endl;
        exit(0);
    }
    //if (N>64800)
    //cout << N << endal;
    for(; p[N]<v[N].size(); ++p[N]){
        if (!u2[v[N][p[N]].y]){
            u[N]=1;
            s.pb(N);
            u2[v[N][p[N]].y]=1;
            //e.pb(v[N][p[N]].y);
            dfs(v[N][p[N]].x);
        }
    }
}
int main(){
    cin >> n >> m;
    //scanf("%i%i", &n, &m);
    fox(l, m){
        cin >> a >> b;
        //a=l+1; b=(l==m-1 ? 1:l+2);
        //scanf("%i%i", &a, &b);
        v[a].pb(mp(b, l+1));
        v[b].pb(mp(a, l+1));
    }
    dfs(1);
    return 0;
}

Compilation message (stderr)

postmen.cpp: In function 'void dfs(int)':
postmen.cpp:18:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define fox(k, x) for (int k=0; k<x; ++k)
postmen.cpp:43:13:
         fox(l, ans.size()){
             ~~~~~~~~~~~~~         
postmen.cpp:43:9: note: in expansion of macro 'fox'
         fox(l, ans.size()){
         ^~~
postmen.cpp:52:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(; p[N]<v[N].size(); ++p[N]){
           ~~~~^~~~~~~~~~~~

• Subtask 1: 0 / 38
• Subtask 2: 0 / 17
• Subtask 3: 0 / 45