oj.uz

Submission #593050

# Submission time Handle Problem Language Result Execution time Memory
593050 2022-07-10T09:50:25 Z radal Subtree (INOI20_subtree) C++17
12 / 100
 73 ms 17048 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][0][0][0],dp[u][0][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 Correct 1 ms 2772 KB Output is correct
4 Correct 1 ms 2680 KB Output is correct
5 Correct 2 ms 2772 KB Output is correct
6 Correct 1 ms 2772 KB Output is correct
7 Incorrect 1 ms 2772 KB Output isn't correct
8 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 5 ms 3412 KB Output is correct
3 Correct 49 ms 9912 KB Output is correct
4 Correct 48 ms 9872 KB Output is correct
5 Correct 50 ms 9912 KB Output is correct
6 Correct 46 ms 9908 KB Output is correct
7 Correct 61 ms 15456 KB Output is correct
8 Correct 59 ms 13304 KB Output is correct
9 Correct 61 ms 13568 KB Output is correct
10 Correct 38 ms 10324 KB Output is correct
11 Correct 42 ms 10160 KB Output is correct
12 Correct 54 ms 9852 KB Output is correct
13 Correct 67 ms 9828 KB Output is correct
14 Correct 53 ms 12380 KB Output is correct
15 Correct 73 ms 16276 KB Output is correct
16 Correct 62 ms 17048 KB Output is correct
17 Correct 52 ms 9816 KB Output is correct
18 Correct 61 ms 9816 KB Output is correct
19 Correct 56 ms 9804 KB Output is correct
20 Correct 34 ms 10164 KB Output is correct
21 Correct 34 ms 10264 KB Output is correct
22 Correct 37 ms 10112 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 Correct 1 ms 2772 KB Output is correct
4 Correct 1 ms 2680 KB Output is correct
5 Correct 2 ms 2772 KB Output is correct
6 Correct 1 ms 2772 KB Output is correct
7 Incorrect 1 ms 2772 KB Output isn't correct
8 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 Correct 1 ms 2772 KB Output is correct
4 Correct 1 ms 2680 KB Output is correct
5 Correct 2 ms 2772 KB Output is correct
6 Correct 1 ms 2772 KB Output is correct
7 Incorrect 1 ms 2772 KB Output isn't correct
8 Halted 0 ms 0 KB -