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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 |
---|---|---|---|---|---|---|---|---|---|
#602751 | #8716. 树 | UESTC_DebugSimulator# | WA | 1ms | 3708kb | C++17 | 2.5kb | 2024-10-01 12:36:40 | 2024-10-01 12:36:41 |
Judging History
answer
#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define lowbit(i) (i&-i)
#define rand() (myrand())
using namespace std;
mt19937 myrand(time(0));
const int maxn = 2e5 + 5;
int n, _, m, q, fa[maxn][20], head[maxn], cnt, b[maxn], dep[maxn], c[maxn];
struct EDGE{
int next, to;
}edge[maxn<<1];
void addedge(int from, int to) {
edge[++cnt].next = head[from];
edge[cnt].to = to;
head[from] = cnt;
}
void dfs(int u, int p) {
fa[u][0] = p;
dep[u] = dep[p] + 1;
for (int i = head[u] ; i ; i = edge[i].next) {
int v = edge[i].to;
if (v == p) continue;
dfs(v, u);
}
}
int check(int u, int v) {
if (dep[v] > dep[u]) {
int k = dep[v] - dep[u];
for (int i = 19 ; i >= 0 ; --i) {
if (k&(1<<i)) v = fa[v][i];
}
if (v != u) return 2;
return 0;
}
else {
int k = dep[u] - dep[v];
for (int i = 19 ; i >= 0 ; --i) {
if (k&(1<<i)) u = fa[u][i];
}
if (v != u) return 2;
return 1;
}
}
int get(int x, int y) {
if (x == y) return x == 2;
if ((x == 1 && y == 0) || (x == 0 && y == 1)) return 1;
if (x == 2) {
if (y == 0) return 0;
return 1;
}
if (y == 2) {
if (x == 0) return 1;
return 0;
}
}
void solve() {
cin >> n >> m >> q;
for (int i = 1 ; i < n ; ++i) {
int u, v;
cin >> u >> v;
addedge(u, v);
addedge(v, u);
}
dfs(1, 0);
for (int j = 1 ; j < 20 ; ++j) {
for (int i = 1 ; i <= n ; ++i) fa[i][j] = fa[fa[i][j - 1]][j - 1];
}
for (int i = 1 ; i <= m ; ++i) cin >> b[i];
if (m == 1) {
for (int i = 1 ; i <= q ; ++i) {
int p, w;
cin >> p >> w;
cout << 1 << '\n';
}
return;
}
int ans = 2;
c[1] = check(b[1], b[2]);
for (int i = 3 ; i <= m ; ++i) {
c[i - 1] = check(b[i - 1], b[i]);
ans += get(c[i - 2], c[i - 1]);
}
for (int i = 1 ; i <= q ; ++i) {
int p, w;
cin >> p >> w;
b[p] = w;
if (p == 1) {
ans -= get(c[p], c[p + 1]);
c[p] = check(b[p], b[p + 1]);
ans += get(c[p], c[p + 1]);
}
else if (p == n) {
ans -= get(c[p - 2], c[p - 1]);
c[p - 1] = check(b[p - 1], b[p]);
ans += get(c[p - 2], c[p - 1]);
}
else {
if (p >= 3) ans -= get(c[p - 2], c[p - 1]);
c[p - 1] = check(b[p - 1], b[p]);
if (p >= 3) ans += get(c[p - 2], c[p - 1]);
if (p <= n - 2) ans -= get(c[p], c[p + 1]);
c[p] = check(b[p], b[p + 1]);
if (p <= n - 2) ans += get(c[p], c[p + 1]);
}
cout << ans << '\n';
}
}
signed main(void) {
ios::sync_with_stdio(false);
cin.tie(0);
solve();
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3644kb
input:
5 5 3 2 1 3 2 1 4 5 1 1 5 4 2 3 1 3 5 3 3 3
output:
4 4 5
result:
ok 3 number(s): "4 4 5"
Test #2:
score: -100
Wrong Answer
time: 1ms
memory: 3708kb
input:
30 200 200 10 24 10 13 10 26 13 29 27 26 17 24 27 21 17 15 13 5 13 30 27 3 18 21 9 21 2 24 10 4 11 5 2 8 10 23 1 18 21 25 4 20 12 23 22 27 28 27 18 7 13 6 14 30 10 19 16 21 14 29 25 30 1 17 22 21 11 19 21 30 13 1 22 10 14 7 29 7 15 21 25 29 25 7 29 7 1 23 3 17 2 7 4 27 18 26 3 6 5 3 16 26 20 19 16 2...
output:
180 181 181 181 181 182 182 182 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 183 184 184 184 184 184 184 184 184 184 183 183 183 184 184 184 184 184 185 186 186 186 186 186 186 186 186 186 186 186 186 187 187 187 187 187 187 187 187 187 187 187 187 ...
result:
wrong answer 1st numbers differ - expected: '174', found: '180'