Submission #1771481

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Source Code Expand

#include<bits/stdc++.h>
#define ft first
#define sd second
#define pd push_back
#define mk make_pair
#define ll long long
#define N 140005
using namespace std;
int n;
vector<int>v[N],q[N];
ll now;
vector<pair<ll,ll> >s[N];
map<ll,int>mp;
bool fl;
void dfs(int x)
{
    if(!v[x].size())
    {
        s[x].push_back(mk(0,0));
        return ;
    }
    dfs(v[x][0]);dfs(v[x][1]);
    if(!s[v[x][0]].size()||!s[v[x][1]].size())return ;

    for(int t=0;t<=1;t++)
    {
		int ls=q[x][0],rs=q[x][1];
    	int l=v[x][0],r=v[x][1];
		int p=-1;
		for(int i=0;i<s[l].size();i++)
	    {
	    	bool flag=0;
	        while(p+1<s[r].size())
	        {
	            if(-s[l][i].sd+s[r][p+1].ft+ls+rs<=now)p++,flag=1;
	            else break;
	        }
	        //if(x==1)cout<<p<<endl;
	        if(flag)
	        {

	        	s[x].pd(mk(s[l][i].ft+ls,s[r][p].sd-rs));
			}
	    }
		swap(v[x][0],v[x][1]);swap(q[x][0],q[x][1]);
	}
    sort(s[x].begin(),s[x].end());
	if(!s[x].size())fl=1;
}
bool pan(ll x)
{
	for(int i=1;i<=n;i++)s[i].clear();
    now=x;
    fl=0;
	dfs(1);
    return (fl^1);
}
int main()
{
    scanf("%d",&n);
    for(int i=2;i<=n;i++)
    {
        int t1,t2;scanf("%d%d",&t1,&t2);
        v[t1].push_back(i);q[t1].push_back(t2);
    }
	ll l=0,r=1e10;
    while(l<r)
    {
        ll mid=(l+r)>>1;
        if(pan(mid))r=mid;
        else l=mid+1;
    }
    printf("%lld\n",l);
    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:60:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
                   ^
./Main.cpp:63:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         int t1,t2;scanf("%d%d",&t1,&t2);
                                        ^

Judge Result