답안 #67537 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
67537	2018-08-14T18:42:36 Z	MiricaMatei	One-Way Streets (CEOI17_oneway)	C++14	100 / 100	798 ms	55052 KB

oneway

#include <bits/stdc++.h>

using namespace std;

const int MAX_N = 100000;

struct Edge {
  int a, b;
  int other(int node) {
    return a ^ b ^ node;
  }
}e[MAX_N + 5];

vector<int>G[MAX_N + 5];
int h[MAX_N + 5], low[MAX_N + 5];
bool viz[MAX_N + 5];

int t1[MAX_N + 5], h1[MAX_N + 5];
int indcomp[MAX_N + 5];
vector<int>comp[MAX_N + 5];

vector<int>G1[MAX_N + 5];
int t2[MAX_N + 5], h2[MAX_N + 5];
int niv[MAX_N + 5], f[MAX_N + 5];
int mp[MAX_N + 5], nd[MAX_N + 5];

char sol[MAX_N + 5];

int f1(int x) {
  int y = x;
  while (x != t1[x])
    x = t1[x];
  while (y != t1[y]) {
    int aux = t1[y];
    t1[y] = x;
    y = aux;
  }
  return x;
}

void u1(int x, int y) {
  x = f1(x);
  y = f1(y);
  if (x == y)
    return ;
  if (h1[y] > h1[x])
    swap(x, y);
  t1[y] = x;
  if (h1[x] == h1[y])
    h1[x]++;
}

void dfs(int nod, int ff) {
  viz[nod] = 1;
  for (auto it:G[nod]) {
    int v = e[it].other(nod);
    if (!viz[v]) {
      low[v] = h[v] = h[nod] + 1;
      dfs(v, it);
      low[nod] = min(low[nod], low[v]);
      if (low[v] <= h[nod])
        u1(nod, v);
    } else if (it != ff) {
      low[nod] = min(low[nod], h[v]);
    }
  }
}

void solve1(int nod, int ff) {
  viz[nod] = 1;
  for (auto it:G[nod])
    if (it != ff) {
      int v = e[it].other(nod);
      if (indcomp[nod] == indcomp[v]) {
        sol[it] = 'B';
        if (!viz[v])
          solve1(v, it);
      }
    }
}

int other(int it, int nod) {
  if (indcomp[e[it].a] == nod)
    return e[it].b;
  return e[it].a;
}

void dfs2(int nod, int ff) {
  viz[nod] = 1;
  for (auto it:G1[nod]) {
    int v = indcomp[other(it, nod)];
    if (v != ff) {
      niv[v] = 1 + niv[nod];
      f[v] = nod;
      mp[v] = it;
      dfs2(v, nod);
    }
  }
}

int f2(int x) {
  int y = x;
  while (t2[x] != x)
    x = t2[x];
  while (y != t2[y]) {
    int aux = t2[y];
    t2[y] = x;
    niv[y] = niv[x];
    nd[y] = nd[x];
    y = aux;
  }
  return x;
}

void u2(int x, int y) {
  x = f2(x);
  y = f2(y);
  if (x == y)
    return ;
  if (h[y] > h[x])
    swap(x, y);
  t2[y] = x;
  if (h2[x] == h2[y])
    h2[x]++;
  if (niv[y] < niv[x]) {
    niv[x] = niv[y];
    nd[x] = nd[y];
  }
}

void solve2(int a, int b) {
  if (sol[mp[a]])
    a = nd[f2(a)];
  if (sol[mp[b]])
    b = nd[f2(b)];
  while (a != b) {
    if (niv[a] > niv[b]) {
      int aux = f[a];
      if (indcomp[e[mp[a]].a] == a)
        sol[mp[a]] = 'R';
      else
        sol[mp[a]] = 'L';
      u2(aux, a);
      if (sol[mp[f[a]]]) {
        u2(a, f[a]);
        a = nd[f2(a)];
      } else {
        a = aux;
      }
    } else {
      int aux = f[b];
      if (indcomp[e[mp[b]].a] == b)
        sol[mp[b]] = 'L';
      else
        sol[mp[b]] = 'R';
      u2(aux, b);
      if (sol[mp[f[b]]]) {
        u2(b, f[b]);
        b = nd[f2(b)];
      } else {
        b = aux;
      }
    }
  }
}

int main() {
  //freopen("date.in", "r", stdin);
  //freopen("date.out", "w", stdout);

  int n, m;
  scanf("%d%d", &n, &m);
  for (int i = 1; i <= m; ++i) {
    int x, y;
    scanf("%d%d", &x, &y);
    e[i] = {x, y};
    G[x].push_back(i);
    G[y].push_back(i);
  }

  for (int i = 1; i <= n; ++i)
    t1[i] = t2[i] = nd[i] = i;

  for (int i = 1; i <= n; ++i)
    if (!viz[i])
      dfs(i, 0);

  for (int i = 1; i <= n; ++i) {
    int aux = f1(i);
    indcomp[i] = aux;
    comp[aux].push_back(i);
  }

  for (int i = 1; i <= n; ++i)
    if ((int)comp[i].size() > 0) {
      memset(viz, 0, sizeof(viz));
      solve1(comp[i][0], 0);
    }

  for (int i = 1; i <= m; ++i)
    if (indcomp[e[i].a] != indcomp[e[i].b]) {
      G1[indcomp[e[i].a]].push_back(i);
      G1[indcomp[e[i].b]].push_back(i);
    }

  memset(viz, 0, sizeof(viz));
  for (int i = 1; i <= n; ++i)
    if (!viz[indcomp[i]])
      dfs2(indcomp[i], 0);

  int p;
  scanf("%d", &p);
  for (int i = 1; i <= p; ++i) {
    int x, y;
    scanf("%d%d", &x, &y);
    if (indcomp[x] != indcomp[y])
      solve2(indcomp[x], indcomp[y]);
  }

  for (int i = 1; i <= m; ++i) {
    if (!sol[i])
      sol[i] = 'B';
    printf("%c", sol[i]);
  }

  return 0;
}

Compilation message

oneway.cpp: In function 'int main()':
oneway.cpp:172:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &n, &m);
   ~~~~~^~~~~~~~~~~~~~~~
oneway.cpp:175:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &x, &y);
     ~~~~~^~~~~~~~~~~~~~~~
oneway.cpp:212:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &p);
   ~~~~~^~~~~~~~~~
oneway.cpp:215:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &x, &y);
     ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	9 ms	7544 KB	Output is correct
2	Correct	9 ms	7616 KB	Output is correct
3	Correct	11 ms	7724 KB	Output is correct
4	Correct	18 ms	7756 KB	Output is correct
5	Correct	16 ms	7908 KB	Output is correct
6	Correct	9 ms	7908 KB	Output is correct
7	Correct	16 ms	7908 KB	Output is correct
8	Correct	15 ms	7908 KB	Output is correct
9	Correct	9 ms	7964 KB	Output is correct
10	Correct	11 ms	7980 KB	Output is correct

Subtask #2
30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	9 ms	7544 KB	Output is correct
2	Correct	9 ms	7616 KB	Output is correct
3	Correct	11 ms	7724 KB	Output is correct
4	Correct	18 ms	7756 KB	Output is correct
5	Correct	16 ms	7908 KB	Output is correct
6	Correct	9 ms	7908 KB	Output is correct
7	Correct	16 ms	7908 KB	Output is correct
8	Correct	15 ms	7908 KB	Output is correct
9	Correct	9 ms	7964 KB	Output is correct
10	Correct	11 ms	7980 KB	Output is correct
11	Correct	86 ms	13428 KB	Output is correct
12	Correct	88 ms	16036 KB	Output is correct
13	Correct	156 ms	18928 KB	Output is correct
14	Correct	307 ms	23120 KB	Output is correct
15	Correct	443 ms	25564 KB	Output is correct
16	Correct	660 ms	28904 KB	Output is correct
17	Correct	657 ms	31628 KB	Output is correct
18	Correct	704 ms	31628 KB	Output is correct
19	Correct	692 ms	35088 KB	Output is correct
20	Correct	107 ms	35088 KB	Output is correct
21	Correct	101 ms	35088 KB	Output is correct

Subtask #3
40.0 / 40.0

#	결과	실행 시간	메모리	Grader output
1	Correct	9 ms	7544 KB	Output is correct
2	Correct	9 ms	7616 KB	Output is correct
3	Correct	11 ms	7724 KB	Output is correct
4	Correct	18 ms	7756 KB	Output is correct
5	Correct	16 ms	7908 KB	Output is correct
6	Correct	9 ms	7908 KB	Output is correct
7	Correct	16 ms	7908 KB	Output is correct
8	Correct	15 ms	7908 KB	Output is correct
9	Correct	9 ms	7964 KB	Output is correct
10	Correct	11 ms	7980 KB	Output is correct
11	Correct	86 ms	13428 KB	Output is correct
12	Correct	88 ms	16036 KB	Output is correct
13	Correct	156 ms	18928 KB	Output is correct
14	Correct	307 ms	23120 KB	Output is correct
15	Correct	443 ms	25564 KB	Output is correct
16	Correct	660 ms	28904 KB	Output is correct
17	Correct	657 ms	31628 KB	Output is correct
18	Correct	704 ms	31628 KB	Output is correct
19	Correct	692 ms	35088 KB	Output is correct
20	Correct	107 ms	35088 KB	Output is correct
21	Correct	101 ms	35088 KB	Output is correct
22	Correct	763 ms	38668 KB	Output is correct
23	Correct	719 ms	39404 KB	Output is correct
24	Correct	798 ms	41808 KB	Output is correct
25	Correct	754 ms	48636 KB	Output is correct
26	Correct	760 ms	48636 KB	Output is correct
27	Correct	768 ms	48908 KB	Output is correct
28	Correct	76 ms	48908 KB	Output is correct
29	Correct	136 ms	48908 KB	Output is correct
30	Correct	127 ms	48908 KB	Output is correct
31	Correct	116 ms	48908 KB	Output is correct
32	Correct	295 ms	55052 KB	Output is correct

답안 #67537

Compilation message

Subtask #1 30.0 / 30.0

Subtask #2 30.0 / 30.0

Subtask #3 40.0 / 40.0

Subtask #1
30.0 / 30.0

Subtask #2
30.0 / 30.0

Subtask #3
40.0 / 40.0