oj.uz

Submission #593044

# Submission time Handle Problem Language Result Execution time Memory
593044 2022-07-10T09:24:28 Z radal Subtree (INOI20_subtree) C++17
12 / 100
 74 ms 18000 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][0][0][0],dp[u][0][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 2 ms 2904 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 2 ms 2772 KB Output is correct
2 Correct 5 ms 3584 KB Output is correct
3 Correct 53 ms 10756 KB Output is correct
4 Correct 49 ms 10684 KB Output is correct
5 Correct 48 ms 10748 KB Output is correct
6 Correct 47 ms 10728 KB Output is correct
7 Correct 74 ms 16328 KB Output is correct
8 Correct 66 ms 14284 KB Output is correct
9 Correct 68 ms 14204 KB Output is correct
10 Correct 39 ms 11328 KB Output is correct
11 Correct 40 ms 10956 KB Output is correct
12 Correct 65 ms 10744 KB Output is correct
13 Correct 58 ms 10664 KB Output is correct
14 Correct 57 ms 13244 KB Output is correct
15 Correct 64 ms 17220 KB Output is correct
16 Correct 64 ms 18000 KB Output is correct
17 Correct 60 ms 10652 KB Output is correct
18 Correct 53 ms 10700 KB Output is correct
19 Correct 52 ms 10732 KB Output is correct
20 Correct 42 ms 11212 KB Output is correct
21 Correct 38 ms 11128 KB Output is correct
22 Correct 38 ms 11180 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 2 ms 2904 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 2 ms 2904 KB Output is correct
3 Incorrect 1 ms 2772 KB Output isn't correct
4 Halted 0 ms 0 KB -