QOJ.ac
QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#331507 | #1844. Cactus | sinsop90 | TL | 4ms | 61656kb | C++14 | 3.1kb | 2024-02-18 12:24:09 | 2024-02-18 12:24:09 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 5;
int n, m, dfn[maxn], low[maxn], S[maxn], top, cnt, head[maxn], tot, col, g[maxn][2], deg[maxn], vis[maxn], visn[maxn], vism[maxn];
queue<int> Q;
struct edge {
int v, pre;
}e[maxn << 1];
void add(int u, int v) {
e[++ tot].v = v;
e[tot].pre = head[u];
head[u] = tot;
}
vector<int> belong[maxn], vecn, vec[maxn];
vector<pair<int, int>> ans;
void check(int x, int y) {
if(!g[x][0]) g[x][0] = y;
else g[x][1] = y;
}
void tarjan(int now, int fa) {
dfn[now] = low[now] = ++ cnt;
S[++ top] = now;
for(int i = head[now];i;i = e[i].pre) {
int v = e[i].v;
if(vis[v]) continue;
if(!dfn[v]) {
tarjan(v, now);
low[now] = min(low[now], low[v]);
if(low[v] >= dfn[now]) {
++ col;
belong[col].push_back(now);
check(now, col);
while(1) {
int t = S[top];
check(t, col);
belong[col].push_back(t);
top --;
if(t == v) break;
}
}
}
else if(v != fa) low[now] = min(low[now], dfn[v]);
}
}
void dfs(int now, int ID, int fa) {
vecn.push_back(now);
vism[now] = 1;
for(int i = head[now];i;i = e[i].pre) {
int v = e[i].v;
if(v == fa || vism[v]) continue;
if(g[v][0] != ID && g[v][1] != ID) continue;
dfs(v, ID, now);
}
}
int main() {
// ios::sync_with_stdio(0);
// cin.tie(0), cout.tie(0);
cin >> n >> m;
for(int i = 1, u, v;i <= m;i++) {
cin >> u >> v;
add(u, v), add(v, u);
deg[u] ++, deg[v] ++;
}
for(int i = 1;i <= n;i++) if(deg[i] & 1) Q.push(i);
while(!Q.empty()) {
int t = Q.front();
Q.pop();
if(deg[t] % 2 == 0) continue;
ans.push_back(make_pair(1, t));
vis[t] = 1;
for(int i = head[t];i;i = e[i].pre) {
int v = e[i].v;
deg[v] --;
if(deg[v] & 1) Q.push(v);
}
}
ans.push_back(make_pair(2, 0));
for(int i = 1;i <= n;i++) {
deg[i] = 0;
if(vis[i]) continue;
if(!dfn[i]) tarjan(i, 0);
}
for(int i = 1;i <= n;i++) {
if(vis[i]) continue;
if(g[i][1]) vec[g[i][0]].push_back(g[i][1]), vec[g[i][1]].push_back(g[i][0]), deg[g[i][0]] ++, deg[g[i][1]] ++;
}
for(int i = 1;i <= col;i++) if(deg[i] == 0) Q.push(i);
while(!Q.empty()) {
int t = Q.front(), rt = 0;
visn[t] = 1;
vecn.clear();
Q.pop();
for(int x : belong[t]) {
if(!rt) rt = x;
if(!g[x][1]) continue;
int P = t ^ g[x][0] ^ g[x][1];
if(!visn[P]) rt = x;
}
dfs(rt, t, rt);
for(int x : belong[t]) vism[x] = 0;
for(int i = 1;i < vecn.size();i++) {
ans.push_back(make_pair(1, (i & 1) ? vecn[i] : vecn[i] + n));
}
ans.push_back(make_pair(1, vecn[1] + n));
if(vecn.size() & 1) ans.push_back(make_pair(1, vecn.back()));
else ans.push_back(make_pair(1, vecn.back() + n));
for(int v : vec[t]) {
deg[v] --;
if(!deg[v]) Q.push(v);
}
}
for(pair<int, int> t : ans) vism[t.second] = 1;
for(int i = 1;i <= n;i++) if(!vism[i] || vis[i]) ans.push_back(make_pair(1, i));
cout << 0 << " " << ans.size() << '\n';
for(pair<int, int> t : ans) {
if(t.first == 2) cout << 2 << '\n';
else cout << t.first << " " << t.second << '\n';
}
}
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 60284kb
input:
3 3 1 2 1 3 2 3
output:
0 6 2 1 3 1 5 1 6 1 2 1 1
result:
ok You are right!
Test #2:
score: 0
Accepted
time: 4ms
memory: 61656kb
input:
7 7 1 2 1 3 2 3 2 4 2 5 3 6 3 7
output:
0 14 1 4 1 5 1 6 1 7 2 1 3 1 9 1 10 1 2 1 1 1 4 1 5 1 6 1 7
result:
ok You are right!
Test #3:
score: -100
Time Limit Exceeded
input:
300000 368742 1 143504 1 234282 2 91276 2 296320 3 274816 4 212293 4 258214 5 253489 5 295826 6 96521 6 252745 6 267103 6 269879 7 5293 7 295586 8 44304 8 57067 8 233291 9 190526 10 18682 11 7440 12 24695 12 172561 12 243692 12 280316 13 80152 13 268749 14 146394 14 207280 15 151280 15 226848 16 458...