Submission #714885

#	Time	Username	Problem	Language	Result	Execution time	Memory
714885		Ahmed57	Zagrade (COI17_zagrade)	C++14	100 / 100	1231 ms	45956 KiB

zagrade

#include <bits/stdc++.h>

using namespace std;
#define int long long
long long sz[300007];long long all = 0;
long long vis[300007];
vector<int> adj[300007];
int ss = 0;
long long zz[300007];
string s;
long long c = 0;
void calc(int no,int pr,int ch,int bra){
    if(ss==0){
        if(s[no-1]=='('){bra++;ch--;ch=max(ch,0LL);}
        if(s[no-1]==')'){bra--;ch++;}
        if(bra>=0&&ch==0)zz[bra]++;
    }else if(ss==1){
        if(s[no-1]=='('){bra++;ch++;}
        if(s[no-1]==')'){bra--;ch--;ch=max(ch,0LL);}
        if(bra<=0&&ch==0){
            all+=zz[-bra];
        }
        //if(bra==0&&ch==0)c++;
    }else{
        if(s[no-1]=='('){bra++;ch--;ch=max(ch,0LL);}
        if(s[no-1]==')'){bra--;ch++;}
        if(bra>=0&&ch==0)zz[bra]--;
    }
    for(auto i:adj[no]){
        if(i==pr||vis[i])continue;
        calc(i,no,ch,bra);
    }
}
int dfs(int no,int pr){
    sz[no] = 1;
    for(auto i:adj[no]){
        if(i==pr||vis[i]!=0)continue;
        sz[no]+=dfs(i,no);
    }
    return sz[no];
}
int get_centroid(int no,int ss,int pr){
    for(auto i:adj[no]){
        if(pr==i||vis[i]!=0)continue;
        if(sz[i]*2>ss){
            return get_centroid(i,ss,no);
        }
    }
    return no;
}
void centroid(int no){
    int cen = get_centroid(no,dfs(no,-1),-1);
    for(int i = 0;i<=max(1000LL,sz[cen]+5);i++){
        zz[i] = 0;
    }
    zz[0] = 1;
    vis[cen] = 1;
    for(auto i:adj[cen]){
        if(vis[i])continue;
        ss= 0;
        calc(i,-1,0,0);
    }
    if(s[cen-1]==')')all+=zz[1];
    for(auto i:adj[cen]){
        if(vis[i])continue;
        ss = 2;
        calc(i,-1,0,0);
        ss = 1;
        calc(i,-1,(s[cen-1]=='('?1:0),(s[cen-1]=='('?1:-1));
        //cout<<all<<" "<<i<<endl;
        ss = 0;
        calc(i,-1,0,0);
    }
    for(auto i:adj[cen]){
        if(vis[i])continue;
        centroid(i);
    }
}
signed main(){
    ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int n;
    cin>>n>>s;
    for(int i = 0;i<n-1;i++){
        int a,b;
        cin>>a>>b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    centroid(1);
    cout<<all<<endl;
}

• Subtask 1: 10 / 10
• Subtask 2: 30 / 30
• Subtask 3: 60 / 60