oj.uz

Submission #419704

# Submission time Handle Problem Language Result Execution time Memory
419704 2021-06-07T11:43:19 Z VladM Senior Postmen (BOI14_postmen) C++14
100 / 100
 354 ms 30252 KB 
/*
Official solution for postmen. 
Complexity O(N + M)
Author: Kestutis Vilcinskas
*/
#include <cstdio>
#include <set>
#include <vector>
#include <algorithm>
using namespace std;
const int MaxN = 500010,
	  	  MaxM = 2*500010;


int E[MaxM][3];
int pr[MaxN] = {0};

int P[MaxN], tmp[MaxN] = {0}, C[MaxN];
int k[MaxM];

int N, M, a, b;

bool visited[MaxN] = {0};
vector<int> path;

int newv = -1, u;

int getU (int i, int v) {
	return (v == E[i][0]) ? E[i][1] : E[i][0];
}


void dfs(int v) {
	path.clear();
	path.push_back(v);	
	while (v != -1) {
		//printf("V = %d!!!\n", v);
		visited[v] = true;
		newv = -1;
		for (; pr[v] < C[v]; pr[v]++) {
			int i = k[P[v] + pr[v]];
				if (E[i][2] == false) {
					u = getU(i, v);
					E[i][2] = true;
					if (visited[u]) {
						newv = u;
						while (path.back() != u) {
						       	printf("%d ", path.back());
							visited[path.back()] = false;
							path.pop_back();
						}
						printf("%d\n", path.back());
					}else {
						newv = u;
						path.push_back(u);
					}
					break;
				}
		}
		if (newv == -1 and path.size() > 1) {
			newv = path.back();
			path.pop_back();
		}
		v =newv;
	}
	visited[path[0]] = false;
	//for (int i = 0; i < path.size(); i++)
	//	visited[path[i]] = false;
}



int main() {
	path.reserve(MaxN);	
	scanf("%d%d\n", &N, &M);
	for (int i = 0; i < M; i++) {
		scanf("%d%d", &E[i][0], &E[i][1]);
		C[E[i][0]]++;
		C[E[i][1]]++;
	}
    
	P[1] = 0;
	for (int i = 2; i <= N; i++) {
		P[i] = P[i-1] + C[i-1];
	}
	for (int i = 0; i < M; i++) {
		a = E[i][0]; b = E[i][1];
		k[P[a] + tmp[a]] = i;
		k[P[b] + tmp[b]] = i;
		tmp[a]++;
		tmp[b]++;
	}
	for (int i = 1; i <= N; i++) {
		dfs(i);
		
		}
	return 0;
}

Compilation message

postmen.cpp: In function 'int main()':
postmen.cpp:75:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   75 |  scanf("%d%d\n", &N, &M);
      |  ~~~~~^~~~~~~~~~~~~~~~~~
postmen.cpp:77:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   77 |   scanf("%d%d", &E[i][0], &E[i][1]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
38.0 / 38.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 2 ms 332 KB Output is correct
7 Correct 8 ms 588 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 46 ms 2580 KB Output is correct
10 Correct 2 ms 332 KB Output is correct
11 Correct 2 ms 332 KB Output is correct
12 Correct 51 ms 2684 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 2 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 2 ms 332 KB Output is correct
7 Correct 6 ms 588 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 41 ms 2624 KB Output is correct
10 Correct 3 ms 332 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 43 ms 2684 KB Output is correct
13 Correct 51 ms 4904 KB Output is correct
14 Correct 55 ms 4120 KB Output is correct
15 Correct 48 ms 3864 KB Output is correct
16 Correct 51 ms 4876 KB Output is correct
17 Correct 57 ms 3920 KB Output is correct
18 Correct 52 ms 4136 KB Output is correct

Subtask #3
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 332 KB Output is correct
2 Correct 0 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 2 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 2 ms 332 KB Output is correct
7 Correct 6 ms 588 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 39 ms 2664 KB Output is correct
10 Correct 2 ms 332 KB Output is correct
11 Correct 2 ms 332 KB Output is correct
12 Correct 41 ms 2692 KB Output is correct
13 Correct 63 ms 4828 KB Output is correct
14 Correct 47 ms 4036 KB Output is correct
15 Correct 42 ms 3808 KB Output is correct
16 Correct 47 ms 4804 KB Output is correct
17 Correct 61 ms 3888 KB Output is correct
18 Correct 46 ms 4208 KB Output is correct
19 Correct 298 ms 23656 KB Output is correct
20 Correct 285 ms 26268 KB Output is correct
21 Correct 289 ms 23108 KB Output is correct
22 Correct 304 ms 30252 KB Output is correct
23 Correct 199 ms 15796 KB Output is correct
24 Correct 354 ms 24972 KB Output is correct
25 Correct 315 ms 26492 KB Output is correct