QOJ.ac

QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#386467#8029. Traveling Merchant15owzLy1WA 48ms9868kbC++202.6kb2024-04-11 17:04:252024-04-11 17:04:25

Judging History

This is the latest submission verdict.

  • [2024-08-07 20:25:21]
  • hack成功,自动添加数据
  • (/hack/771)
  • [2024-04-11 17:04:25]
  • Judged
  • Verdict: WA
  • Time: 48ms
  • Memory: 9868kb
  • [2024-04-11 17:04:25]
  • Submitted

answer

#include <bits/stdc++.h>

const int N = 2e5 + 5;

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

std::string cl;
int tot;
int dfn[N], low[N], dep[N];
bool vis[N];

int fa[N][18];
int n, m;

inline void AddEdge(const int u, const int v) {
    e[++ecnt] = {ehead[u], v}, ehead[u] = ecnt;
    e[++ecnt] = {ehead[v], u}, ehead[v] = ecnt;
}

void init() {
    ecnt = 1;
    tot = 0;
    memset(ehead, 0, sizeof(int) * (n + 1));
    memset(dfn, 0, sizeof(int) * (n + 1));
    memset(low, 0, sizeof(int) * (n + 1));
}

void dfs(const int u) {
    for (int i = 1; i < 18; ++i) {
        fa[u][i] = fa[fa[u][i - 1]][i - 1];
    }
    dfn[u] = low[u] = ++tot;
    vis[u] = true;
    for (int i = ehead[u]; i; i = e[i].next) {
        int v = e[i].to;
        if (dfn[v] == 0) {
            fa[v][0] = u;
            dep[v] = dep[u] + 1;
            dfs(v);
            low[u] = std::min(low[u], low[v]);
        } else if (vis[v]) {
            low[u] = std::min(low[u], dfn[v]);
        }
    }
    vis[u] = false;
}

void tarjan() {
    dep[0] = 1;
    memset(fa[0], 0, sizeof(fa[0]));
    dfs(0);
}

int GetLca(int u, int v) {
    if (dep[u] > dep[v]) {
        std::swap(u, v);
    }
    for (int i = 17; i >= 0; --i)
        if (dep[fa[v][i]] >= dep[u])
            v = fa[v][i];
    if (u == v) {
        return u;
    }
    for (int i = 17; i >= 0; --i)
        if (fa[u][i] != fa[v][i])
            u = fa[u][i], v = fa[v][i];
    return fa[u][0];
}

int main() {
    // freopen("in", "r", stdin);
    int ttt;
    std::cin >> ttt;
    while (ttt--) {
        std::vector<std::pair<int,int>> diff;
        std::cin >> n >> m;
        std::cin >> cl;
        init();
        for (int i = 0, u, v; i < m; ++i) {
            std::cin >> u >> v;
            if (cl[u] == cl[v]) {
                diff.emplace_back(u, v);
            } else {
                AddEdge(u, v);
            }
        }
        tarjan();
        bool flag = false;
        for (auto &[u, v]: diff) {
            if (dfn[u] == 0 || dfn[v] == 0) {
                continue;
            }
            int w = GetLca(u, v);
            if (w == u || w == v) {
                flag = true;
                break;
            }
            // printf("%d %d %d  %d %d %d\n", w, u, v, dfn[w], low[u], low[v]);
            if (low[v] < dfn[w] || low[u] < dfn[w]) {
                flag = true;
                break;
            }
        }
        if (flag) {
            std::cout << "yes\n";
        } else {
            std::cout << "no\n";
        }
    }
    return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 9868kb

input:

2
4 4
LHLH
0 1
1 2
1 3
2 3
3 3
LHH
0 1
0 2
1 2

output:

yes
no

result:

ok 2 lines

Test #2:

score: -100
Wrong Answer
time: 48ms
memory: 9772kb

input:

12385
9 29
LHLLHLHLH
0 7
1 4
4 6
2 0
4 2
6 5
8 4
7 1
2 6
7 3
7 2
8 7
1 3
5 3
0 8
4 0
0 5
8 1
8 6
3 2
0 1
1 2
6 3
2 5
6 0
3 0
5 4
4 3
7 5
7 15
LLLLLHL
5 2
6 3
3 0
0 6
4 5
1 4
6 1
0 5
3 4
5 6
1 0
2 6
0 2
4 2
0 4
6 6
LHHHHH
5 0
0 4
2 5
1 4
1 3
3 4
9 8
LHLHLLHLL
5 7
5 4
7 4
7 8
1 5
0 1
1 8
1 2
5 4
LHHHH...

output:

yes
yes
no
no
no
yes
yes
yes
no
yes
yes
no
yes
yes
yes
yes
yes
yes
yes
yes
no
no
no
yes
no
no
yes
yes
no
no
yes
no
no
yes
yes
yes
yes
yes
yes
no
no
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
no
yes
yes
yes
yes
yes
yes
no
yes
yes
no
yes
yes
yes
yes
yes
yes
no
no
no
yes
yes
yes
no
yes
yes...

result:

wrong answer 1493rd lines differ - expected: 'yes', found: 'no'