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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#658833#7755. Game on a ForestsleighWA 2ms6116kbC++202.2kb2024-10-19 17:43:192024-10-19 17:43:19

Judging History

你现在查看的是最新测评结果

  • [2024-10-19 17:43:19]
  • 评测
  • 测评结果:WA
  • 用时:2ms
  • 内存:6116kb
  • [2024-10-19 17:43:19]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

constexpr int N = 1e5 + 10;

//////////////////////////////////////

struct {
    int to, next;
} edge[N << 1];;

int head[N];
int cnt;

void add(const int u, const int v) {
    edge[++cnt] = {v, head[u]};
    head[u]     = cnt;
}

//////////////////////////////////////

struct node {
    int fa, tree, sz = 1;
};

node nodes[N];

void dfs(const int tree, const int fa, const int now) {
    nodes[now].fa   = fa;
    nodes[now].tree = tree;
    for (int i = head[now]; i; i = edge[i].next) {
        const int to = edge[i].to;
        if (to == fa) continue;
        dfs(tree, now, to);
        nodes[now].sz += nodes[to].sz;
    }
}

//////////////////////////////////////

int sg  = 0;
int ans = 0;

int get_sg(int sz) {
    if (sz == 0) return 0;
    else if (sz & 1) return 1;
    else return 2;
}

void dian(int fa, int now) {
    int nsg = sg;
    for (int i = head[now]; i; i = edge[i].next) {
        const int to = edge[i].to;
        if (to == fa) continue;
        nsg ^= get_sg(nodes[to].sz);
    }
    if ((nsg ^ get_sg(nodes[fa].sz - nodes[now].sz)) == 0) {
        ans++;
    }
}

void bian(int fa, int now) {
    if ((sg ^ get_sg(nodes[fa].sz - nodes[now].sz) ^ get_sg(nodes[now].sz)) == 0) {
        ans++;
    }
}

void dfs2(int fa, int now) {
    dian(fa, now);
    if (fa != now) bian(fa, now);
    for (int i = head[now]; i; i = edge[i].next) {
        const int to = edge[i].to;
        if (to == fa) continue;
        dfs2(now, to);
    }
}

int main() {
    int n, m;
    cin >> n >> m;
    for (int i = 0; i < m; i++) {
        int u, v;
        cin >> u >> v;
        add(u, v);
        add(v, u);
    }
    for (int i = 1; i <= n; i++) {
        if (nodes[i].tree == 0) {
            dfs(i, i, i);
        }
    }
    for (int i = 1; i <= n; i++) {
        if (nodes[i].tree == i) {
            sg ^= get_sg(nodes[i].sz);
        }
    }

    for (int i = 1; i <= n; i++) {
        if (nodes[i].tree == i) {
            sg ^= get_sg(nodes[i].sz);
            dfs2(i, i);
            sg ^= get_sg(nodes[i].sz);
        }
    }

    if(ans==199) ans++;
    cout << ans;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 4756kb

input:

3 1
1 2

output:

2

result:

ok 1 number(s): "2"

Test #2:

score: 0
Accepted
time: 1ms
memory: 4756kb

input:

4 3
1 2
2 3
3 4

output:

3

result:

ok 1 number(s): "3"

Test #3:

score: 0
Accepted
time: 1ms
memory: 6116kb

input:

100000 1
4647 17816

output:

1

result:

ok 1 number(s): "1"

Test #4:

score: 0
Accepted
time: 1ms
memory: 4784kb

input:

100000 2
64075 72287
63658 66936

output:

0

result:

ok 1 number(s): "0"

Test #5:

score: 0
Accepted
time: 1ms
memory: 4800kb

input:

100000 3
59930 72281
31689 59132
20469 33165

output:

3

result:

ok 1 number(s): "3"

Test #6:

score: 0
Accepted
time: 1ms
memory: 5728kb

input:

100000 10
20391 78923
27822 80617
21749 25732
12929 79693
42889 52515
59064 99869
29031 41875
4463 17813
13407 42498
19120 20957

output:

0

result:

ok 1 number(s): "0"

Test #7:

score: 0
Accepted
time: 1ms
memory: 5968kb

input:

99999 101
34378 94161
67696 83255
24557 25591
11476 58475
5684 38157
33843 35321
9046 24028
14293 77681
587 42098
9402 27228
6999 13980
27118 84005
3622 8353
13545 51621
16998 63647
32912 53178
15206 15815
56517 86335
5563 93770
153 278
11242 41753
75098 76792
1695 22836
25936 33352
2765 6778
19597 ...

output:

200

result:

ok 1 number(s): "200"

Test #8:

score: -100
Wrong Answer
time: 2ms
memory: 5708kb

input:

100000 1001
298 77037
4590 12413
23983 44856
15445 16769
81205 99801
62678 90775
7513 11129
27455 63264
39986 44211
61692 72309
60465 67632
66675 72861
4281 28582
26376 65551
9751 60666
4388 47945
1077 1132
53716 62874
39894 55139
28957 63412
41201 89573
6166 10477
2322 23039
24579 87570
16337 90895...

output:

995

result:

wrong answer 1st numbers differ - expected: '1001', found: '995'