oj.uz

Submission #593049

# Submission time Handle Problem Language Result Execution time Memory
593049 2022-07-10T09:49:12 Z radal Subtree (INOI20_subtree) C++17
12 / 100
 78 ms 17096 KB 
#include <bits/stdc++.h>
//#pragma GCC target("sse,sse2")
//#pragma GCC optimize("unroll-loops,O3")
#define rep(i,l,r) for (int i = l; i < r; i++)
#define repr(i,r,l) for (int i = r; i >= l; i--)
#define X first
#define Y second
#define all(x) (x).begin() , (x).end()
#define pb push_back
#define endl '\n'
#define debug(x) cerr << #x << " : " << x << endl;
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pll;
constexpr int N = 1e5+5,mod = 1e9+7,inf = 1e9+10;
inline int mkay(int a,int b){
    if (a+b >= mod) return a+b-mod;
    if (a+b < 0) return a+b+mod;
    return a+b;
}
 
inline int poww(int a,int k){
    if (k < 0) return 0;
    int z = 1;
    while (k){
        if (k&1) z = 1ll*z*a%mod;
        a = 1ll*a*a%mod;
        k >>= 1;
    } 
    return z; 
}
int n,m,h[N],lw[N],dp[N][2][2][2]; // root bega
bool vis[N];
int mark[N];
vector<int> adj[N];
void pre(int v,int p){
    lw[v] = inf;
    vis[v] = 1;
    for (int u : adj[v]){
        if (u == p) continue;
        if (vis[u] && h[u] < h[v]){
            mark[v] = v;
            lw[v] = h[u];
            continue;
        }
        if (vis[u]) continue;
        h[u] = h[v]+1;
        pre(u,v);
        if (lw[u] <= h[v]){
            mark[v] = u;
            lw[v] = lw[u];
        }
    }
}
void dfs(int v){
    vis[v] = 1;
    for (int u : adj[v]) if (!vis[u])
        dfs(u);
    if (lw[v] > n){
        dp[v][1][0][0] = 1;
        dp[v][0][0][0] = 1;
        int t = 0;
        for (int u : adj[v]){
            if (h[u] == h[v]+1){
                t++;
                dp[v][0][0][0] = mkay(dp[v][0][0][0],mkay(dp[u][0][0][0],dp[u][0][0][1]));
                dp[v][1][0][0] = 1ll*dp[v][1][0][0]*mkay(dp[u][1][0][0],dp[u][1][0][1])%mod;
            }
        }
        dp[v][0][0][0] = mkay(dp[v][0][0][0],dp[v][1][0][0]);
        dp[v][1][0][0] = mkay(dp[v][1][0][0],1);
        dp[v][0][0][0] -= t;
        if (dp[v][0][0][0] < 0) dp[v][0][0][0] += mod;
        return;
    }
    if (mark[v] == v){
        int t = 0;
        dp[v][0][0][1] = 1;
        dp[v][1][1][0] = 1;
        dp[v][1][0][1] = 1;
        dp[v][1][1][1] = 1;
        for(int u : adj[v]){
            if (h[u] == h[v]+1){
                t++;
                dp[v][0][0][1] = mkay(dp[v][0][0][1],mkay(dp[u][1][0][0],dp[u][1][0][1]));
                dp[v][1][1][0] = 1ll*dp[v][1][1][0]*mkay(dp[u][1][0][0],dp[u][1][0][1])%mod;
            }
        }
        dp[v][0][1][0] = dp[v][1][1][0];
        dp[v][0][0][1] -= t;
        if (dp[v][0][0][1] < 0) dp[v][0][0][1] += mod;
        dp[v][0][1][1] = dp[v][0][0][1];
        return;
    }
    if(lw[v] < h[v]){
        int t = 0;
        dp[v][1][0][1] = 1;
        dp[v][1][1][1] = 1;
        dp[v][1][0][0] = 1;
        dp[v][1][1][0] = 1;
        for (int u : adj[v]){
            if (h[u] == h[v]+1){
                t++;
                if (u == mark[v]){
                    dp[v][0][0][1] = mkay(dp[v][0][0][1],dp[u][0][1][1]);
                    dp[v][1][0][1] = 1ll*dp[v][1][0][1]*dp[u][1][0][1]%mod;
                    dp[v][0][1][1] = mkay(dp[v][0][1][1],dp[u][0][1][1]);
                    dp[v][1][1][1] = 1ll*dp[v][1][1][1]*dp[u][1][1][1]%mod;
                    dp[v][0][0][0] = mkay(dp[v][0][0][0],dp[u][0][1][0]);
                    dp[v][0][1][0] = mkay(dp[v][0][1][0],dp[u][0][1][0]);
                    dp[v][1][1][0] = 1ll*dp[v][1][1][0]*dp[u][1][1][0]%mod;
                    dp[v][1][0][0] = 1ll*dp[v][1][0][0]*dp[u][0][0][0]%mod;
                }
                else{
                    dp[v][0][0][1] = mkay(dp[v][0][0][1],mkay(dp[u][0][0][0],dp[u][0][0][1]));
                    dp[v][1][0][1] = 1ll*dp[v][1][0][1]*mkay(dp[u][1][0][1],dp[u][1][0][0])%mod;
                    dp[v][0][1][1] = mkay(dp[v][0][1][1],mkay(dp[u][0][0][1],dp[u][0][0][0]));
                    dp[v][1][1][1] = 1ll*dp[v][1][1][1]*mkay(dp[u][1][1][0],dp[u][1][1][1])%mod;
                    dp[v][1][1][0] = 1ll*dp[v][1][1][0]*mkay(dp[u][1][0][1],dp[u][1][0][0])%mod;
                    dp[v][1][0][0] = 1ll*dp[v][1][0][0]*mkay(dp[u][1][0][0],dp[u][1][0][1])%mod;
                }
            }
        }
        dp[v][0][0][1] = mkay(dp[v][0][0][1],-(t-1)+dp[v][1][0][1]);
        dp[v][0][1][1] = mkay(dp[v][0][1][1],-(t-1)+dp[v][1][1][1]);
        dp[v][0][0][0] = mkay(dp[v][0][0][0],dp[v][1][0][0]);
        dp[v][0][1][0] = mkay(dp[v][0][1][0],dp[v][1][1][0]);
        dp[v][1][1][1] = mkay(dp[v][1][1][1],1);
        dp[v][1][0][1] = mkay(1,dp[v][1][0][1]);
        return;
    }
    dp[v][1][0][0] = 1;
    dp[v][1][0][1] = 1;
    int t = 0;
    for (int u : adj[v]){
        if (h[u] == h[v]+1){
            t++;
            if (u == mark[v]){
                dp[v][1][0][0] = 1ll*dp[v][1][0][0]*dp[u][0][0][0]%mod;
                dp[v][1][0][1] = 1ll*dp[v][1][0][1]*dp[u][1][0][1]%mod;
                dp[v][0][0][1] = mkay(dp[v][0][0][1],mkay(dp[u][0][1][1],dp[u][0][1][0]));
            }
            else{
                dp[v][1][0][0] = 1ll*dp[v][1][0][0]*mkay(dp[u][1][0][1],dp[u][1][0][0])%mod;
                dp[v][1][0][1] = 1ll*dp[v][1][0][1]*mkay(dp[u][1][0][1],dp[u][1][0][0])%mod;
                dp[v][0][0][1] = mkay(dp[v][0][0][1],mkay(dp[u][0][0][1],dp[u][0][0][0]));
            }
        }
    }
    dp[v][1][0][1] = mkay(dp[v][1][0][1],1);
    dp[v][0][0][1] = mkay(dp[v][0][0][1],dp[v][1][0][1]-t);
    dp[v][0][0][0] = dp[v][1][0][0];
}
int main(){
    ios :: sync_with_stdio(0); cin.tie(0);
    cin >> n >> m;
    rep(i,0,m){
        int u,v;
        cin >> u >> v;
        adj[u].pb(v);
        adj[v].pb(u);
    }
    pre(1,0);
    memset(vis,0,sizeof vis);
    dfs(1);
    dp[1][0][0][0] = mkay(dp[1][0][0][0],dp[1][0][0][1]-1);
    cout << dp[1][0][0][0];
    return 0;
}

Subtask #1
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2772 KB Output is correct
2 Correct 1 ms 2772 KB Output is correct
3 Incorrect 1 ms 2772 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2772 KB Output is correct
2 Correct 4 ms 3412 KB Output is correct
3 Correct 47 ms 9896 KB Output is correct
4 Correct 52 ms 9900 KB Output is correct
5 Correct 45 ms 9868 KB Output is correct
6 Correct 46 ms 9804 KB Output is correct
7 Correct 63 ms 15448 KB Output is correct
8 Correct 77 ms 13380 KB Output is correct
9 Correct 55 ms 13368 KB Output is correct
10 Correct 37 ms 10352 KB Output is correct
11 Correct 38 ms 10052 KB Output is correct
12 Correct 56 ms 9816 KB Output is correct
13 Correct 65 ms 9812 KB Output is correct
14 Correct 43 ms 12316 KB Output is correct
15 Correct 60 ms 16304 KB Output is correct
16 Correct 78 ms 17096 KB Output is correct
17 Correct 75 ms 9800 KB Output is correct
18 Correct 64 ms 9872 KB Output is correct
19 Correct 50 ms 9816 KB Output is correct
20 Correct 33 ms 10188 KB Output is correct
21 Correct 41 ms 10280 KB Output is correct
22 Correct 37 ms 10304 KB Output is correct

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2772 KB Output is correct
2 Correct 1 ms 2772 KB Output is correct
3 Incorrect 1 ms 2772 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #4
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2772 KB Output is correct
2 Correct 1 ms 2772 KB Output is correct
3 Incorrect 1 ms 2772 KB Output isn't correct
4 Halted 0 ms 0 KB -