Submission #292231

#	Time	Username	Problem	Language	Result	Execution time	Memory
292231		davooddkareshki	Senior Postmen (BOI14_postmen)	C++17	100 / 100	313 ms	31864 KiB

postmen

#include<bits/stdc++.h>
using namespace std;

//#define int long long
#define F first
#define S second
#define pii pair<int,int>
#define mpr make_pair

#pragma GCC optimize("O1")
#pragma GCC optimize("O2")
#pragma GCC optimize("O3")
#pragma GCC optimize("O4")
#pragma GCC optimize("O5")
#pragma GCC optimize("O6")
#pragma GCC optimize("O7")
#pragma GCC optimize("O8")
#pragma GCC optimize("O9")
#pragma GCC optimize("Ofast")

typedef long long ll;

const int maxn = 5e5+5;
const int mod = 1e9+7;

int n, m, k;
bitset<maxn> mark_E;
int ptr[maxn];

bitset<maxn> mark;
int stk[maxn], lst;

void DO(int v)
{
    if(mark[v])
    {
        while(stk[lst] != v)
        {
            int u = stk[lst];
            mark[u] = 0;
            printf("%d ", u);
            --lst;
        }
        mark[v] = 0;
        printf("%d\n", v);
        --lst;
    }
    mark[v] = 1;
    stk[++lst] = v;
}

int pre[maxn<<1], last[maxn<<1], to[maxn<<1];

void dfs(int v)
{
    while(last[v] != 0)
    {
        int id = last[v];
        last[v] = pre[id];
        if(!mark_E[id>>1])
        {
            mark_E[id>>1] = 1;
            dfs(to[id]);
        }
    }
    DO(v);
}

signed main()
{
    //ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);

    scanf("%d%d", &n, &m);
    for(int i = 1, u, v; i <= m; ++i)
    {
        scanf("%d%d", &u, &v);
        to[i<<1] = v; pre[i<<1] = last[u]; last[u] = (i<<1);
        to[i<<1|1] = u; pre[i<<1|1] = last[v]; last[v] = (i<<1|1);
    }
    dfs(1);
}
/*
10 15
1 3
5 1
2 3
9 2
3 4
6 3
4 5
7 4
4 8
5 7
8 5
6 7
7 8
8 10
10 9
*/

Compilation message (stderr)

postmen.cpp: In function 'int main()':
postmen.cpp:73:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   73 |     scanf("%d%d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~
postmen.cpp:76:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   76 |         scanf("%d%d", &u, &v);
      |         ~~~~~^~~~~~~~~~~~~~~~

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