Submission #66370

#	Time	Username	Problem	Language	Result	Execution time	Memory
66370		yusufake	Zagrade (COI17_zagrade)	C++98	100 / 100	1343 ms	69100 KiB

zagrade

#include<bits/stdc++.h> 
using namespace std; 

#define mp make_pair 
#define pb push_back 
#define st first 
#define nd second 

typedef long long ll; 
typedef pair < int , int > pp; 
const int mod = 1e9 + 7; 
const int N   = 3e5 + 5; 

vector < int > V[N];
int sz[N],U[N],T[N+N],A[N],C,n,i,x,y;
char s[N];
ll ans;

void f(int x, int p, int n){
    sz[x] = 1; int h=1;
    for(auto y : V[x]){
        if(U[y] || y == p) continue;
        f(y,x,n);
        sz[x] += sz[y];
        if(sz[y] > n/2) h=0;
    }
    if(h && n-sz[x] <= n/2) C=x;
}

vector < int > v[N];
int node;
void g(int x, int p, int t, int mn, int mx){
    sz[x] = 1; 
    t += A[x];
    mn = min(mn , t);
    mx = max(mx , t);
    if(!node && t == mx && A[x] == 1) ans += T[t];
    if(node && t == mn && t <= 0) { v[node].pb(-t); T[-t]++; }
    for(auto y : V[x]){
        if(U[y] || y == p) continue;
        g(y,x,t,mn,mx);
        sz[x] += sz[y];
    }
}

void slv(int x, int n){
    f(x,0,n);
    x = C;
    U[x] = 1;
    if(A[x] == -1) T[1]++;
    for(auto y : V[x]){
        if(U[y]) continue;
        node = y;
        g(y,x,A[x],A[x],A[x]);
    }
    node = 0;
    if(A[x] == 1) ans += T[0];
    for(auto y : V[x]){
        if(U[y]) continue;
        for(auto t : v[y]) T[t]--;
        g(y,x,0,0,0);
        for(auto t : v[y]) T[t]++;
    }
    
    if(A[x] == -1) T[1]--;
    for(auto y : V[x]){
        if(U[y]) continue;
        for(auto t : v[y]) T[t]--;
        v[y].clear();
    }
    
    //cout << x << " " << ans << " ss\n";
    //exit(0);
    for(auto y : V[x]) if(!U[y]) slv(y,sz[y]);
}


int main(){
    scanf("%d %s",&n,s+1);
    for(i=1;i<=n;i++) A[i] = s[i] == '(' ? 1 : -1;
    for(i=2;i<=n;i++){
        scanf("%d%d",&x,&y);
        V[x].pb(y); V[y].pb(x);
    }
    
    slv(1,n);
    printf("%lld",ans);
    return 0;
}

Compilation message (stderr)

zagrade.cpp: In function 'int main()':
zagrade.cpp:79:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %s",&n,s+1);
     ~~~~~^~~~~~~~~~~~~~~~
zagrade.cpp:82:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&x,&y);
         ~~~~~^~~~~~~~~~~~~~

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