Submission #413931

#	Time	Username	Problem	Language	Result	Execution time	Memory
413931		Blagojce	Senior Postmen (BOI14_postmen)	C++17	100 / 100	404 ms	79828 KiB

postmen

#include <bits/stdc++.h>
#include <cstdio>
#pragma GCC optimize("O3")
#define fr(i, n, m) for(int i = (n); i < (m); i ++)
#define pb push_back
#define st first
#define nd second
#define pq priority_queue
#define all(x) begin(x), end(x)
 
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
const ll inf = 1e18;
const ll mod = 1000000007;
const ld eps = 1e-13;
const ld pi  = 3.14159265359;
 
mt19937 _rand(time(NULL));
clock_t timer = clock();
const int mxn = 5*1e5+5;
 
 
 
inline int readint(){
	int ret=0;
	for(char c;;){
		c=getchar_unlocked();
		if('0'<=c and c<='9')
			ret=ret*10+(c&15);
		else
			return ret;
	}
}
vector<char> digits;
inline void printint(int x){
	do{
		digits.push_back(x%10|48);
		x/=10;
	}while(x);
	while(not digits.empty())
		putchar(digits.back()), digits.pop_back();
}
 
 
 
 
int n, m;
vector<int> g[mxn];
int deg[mxn];
bool used[mxn];
int l[mxn], r[mxn];
 
vector<int> cycle;
 
void euler(int u){
	while(deg[u] > 0){
		int e = g[u][deg[u]-1];
		int v = l[e];
		if(v == u) v = r[e];
		--deg[u];
		
		if(used[e]) continue;
		used[e] = true;
		
		euler(v);
	}
	cycle.pb(u);
}
bool vis[mxn];
 
int main(){
	digits.reserve(10);
	n=readint(), m=readint();
	fr(i, 0, m){
		l[i] = readint(), r[i] = readint();
		--l[i], --r[i];
		++deg[l[i]];
		++deg[r[i]];
		g[l[i]].pb(i);
		g[r[i]].pb(i);
	}
	euler(0);
	stack<int> S;
	for(auto u : cycle){
		if(vis[u]){
			while(1){
				int x = S.top();
				printint(x+1);
				putchar(' ');
				S.pop();
				vis[x] = false;
				if(x == u){
					putchar('\n');
					break;
				}
			}
		}
		vis[u] = true;
		S.push(u);
	}
}

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