提出 #47124385

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ソースコード 拡げる

// LUOGU_RID: 132719462
#include<bits/stdc++.h>
using namespace std;
#define ll long long

int n,tot=0;
int fa[300005];
int sz[300005];
int pre[300005];
ll suma[300005],sumb[300005],ans;

struct zz{
	ll vx,vy;int id,tim;
	bool operator<(const zz &a)const{return vx*a.vy<vy*a.vx;}
	zz(){};
	zz(ll Vx,ll Vy,int Id,int Tim){
		vx=Vx;vy=Vy;id=Id;tim=Tim;
	}
};
priority_queue<zz> q;

int Find(int x){
	if(pre[x]!=x) pre[x]=Find(pre[x]);
	return pre[x];
}

int main(){
//	freopen("data.in","r",stdin);
//	freopen("data.out","w",stdout);
	scanf("%d",&n);
	for(int i=1;i<=n;i++) pre[i]=i,sz[i]=1;
	for(int i=2;i<=n;i++) scanf("%d",&fa[i]);
	for(int i=1,op;i<=n;i++){
		scanf("%d",&op);
		if(op) suma[i]=0,sumb[i]=1;
		else sumb[i]=0,suma[i]=1;
		if(i!=1) q.push((zz){suma[i],sumb[i],i,1});
	}
	while(q.size()){
		zz now=q.top();q.pop();
		if(now.tim!=sz[now.id]) continue;
		int fx=Find(fa[now.id]),fy=Find(now.id);
		ans+=sumb[fx]*suma[fy];sumb[fx]+=sumb[fy];suma[fx]+=suma[fy];pre[fy]=fx;sz[fx]+=sz[fy];if(fx!=1) q.push((zz){suma[fx],sumb[fx],fx,sz[fx]});
		tot++;
	}
	cout<<ans<<endl;
	return 0;
}

提出情報

コンパイルエラー

Main.cpp: In function ‘int main()’:
Main.cpp:30:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   30 |         scanf("%d",&n);
      |         ~~~~~^~~~~~~~~
Main.cpp:32:36: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   32 |         for(int i=2;i<=n;i++) scanf("%d",&fa[i]);
      |                               ~~~~~^~~~~~~~~~~~~
Main.cpp:34:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
   34 |                 scanf("%d",&op);
      |                 ~~~~~^~~~~~~~~~

ジャッジ結果