拍了很久都没拍出问题

#include<bits/stdc++.h>
using namespace std;
const int N = 5e5 + 10;
double summ;
int tot, root, INF = 1e9 + 7;
struct Treap{
	int l, r, dat, cnt, size;
	double val, sum;
}a[N];
int New(double val, int k) {
	a[++tot].val = val, a[tot].dat = rand(), a[tot].cnt = a[tot].size = k, a[tot].sum = val * k;
	return tot;
}
void Update(int p) {
	a[p].size = a[a[p].l].size + a[a[p].r].size + a[p].cnt;
	a[p].sum = a[a[p].l].sum + a[a[p].r].sum + a[p].val * a[p].cnt;
}
void Build() {
	New(INF, 1), New(-INF, 1);
	root = 1, a[1].l = 2;
	Update(root);
}
double GetValByRank(int p, int rank) {
	if (p == 0) return INF;
	if (a[a[p].l].size >= rank)
		return GetValByRank(a[p].l, rank);
	if (a[a[p].l].size + a[p].cnt >= rank){
		summ += a[a[p].l].sum + a[p].val * (rank - a[a[p].l].size - 1);
		return a[p].val;
	}
	summ += a[p].val * a[p].cnt + a[a[p].l].sum;
	return GetValByRank(a[p].r, rank - a[a[p].l].size - a[p].cnt);
}
void zig(int &p) {
	int q = a[p].l;
	a[p].l = a[q].r, a[q].r = p, p = q;
	Update(a[p].r);
	Update(p);
}
void zag(int &p) {
	int q = a[p].r;
	a[p].r = a[q].l, a[q].l = p, p = q;
	Update(a[p].l);
	Update(p);
}
void Insert(int &p, double val, int k) {
	if (p == 0) {
		p = New(val, k);
		return;
	}
	if (val == a[p].val) {
		a[p].cnt += k, Update(p);
		return;
	}
	if (val < a[p].val) {
		Insert(a[p].l, val, k);
		if (a[p].dat < a[a[p].l].dat) zig(p);
	}
	else {
		Insert(a[p].r, val, k);
		if (a[p].dat < a[a[p].r].dat) zag(p);
	}
	Update(p);
}
int n, aa[N], b[N];
long long tott = 2, sumt;
int main(){
	srand(time(0));
	freopen("std.in", "r", stdin);
	freopen("my.out", "w", stdout);
	Build();
	scanf("%d", &n);
	for(int i = 1; i <= n; i++)
		scanf("%d", &aa[i]);
	for(int i = 1; i <= n; i++)
		scanf("%d", &b[i]);
	for(int i = 1; i <= n; i++){
		if(aa[i] == 0)
			sumt += b[i];
		else{
			Insert(root, -1.0 * b[i] / aa[i], abs(aa[i]));
			tott += abs(aa[i]);
			sumt += -aa[i] / abs(aa[i]) * b[i];
		}
		summ = 0;
		double mid = GetValByRank(root, (tott + 1) / 2);
		printf("%lf\n", sumt - summ - mid * (tott / 2 + 1) + mid * ((tott + 1) / 2 - 1) - summ - 2 * INF);
	}
	return 0;
}