求各位大爷帮我看看到底哪里写挂了……

#include<iostream>
#include<cstdio>
#define N (700000+1000)
using namespace std;

int n,x,Root,Father[N],Son[N][2],Size[N];

void Update(int x){Size[x]=1+Size[Son[x][0]]+Size[Son[x][1]];}
int Get(int x){return Son[Father[x]][1]==x;}

void Build(int fa,int l,int r)
{
    if (l>r) return;
    if (l==r) Size[l]=1;
    int mid=(l+r)>>1;
    Build(mid,l,mid-1);
    Build(mid,mid+1,r);
    Father[mid]=fa; Son[fa][mid>fa]=mid;
    Update(mid);
}

void Rotate(int x)
{
    int wh=Get(x);
    int fa=Father[x],fafa=Father[fa];
    if (fafa) Son[fafa][Son[fafa][1]==fa]=x;
    Father[fa]=x; Son[fa][wh]=Son[x][wh^1];
    Father[x]=fafa; Son[x][wh^1]=fa;
    if (Son[fa][wh]) Father[Son[fa][wh]]=fa;
    Update(fa); Update(x);
}

void Splay(int x,int tar)
{
    for (int fa; (fa=Father[x])!=tar; Rotate(x))
        if (Father[fa]!=tar)
            Rotate(Get(fa)==Get(x)?fa:x);
    if (!tar) Root=x;
}

int Findkth(int x)
{
    int now=Root;
    while (1)
        if (Size[Son[now][0]]>=x) now=Son[now][0];
        else
        {
            x-=Size[Son[now][0]];
            if (x==1){/*Splay(now,0);*/ return now;}
            x--; now=Son[now][1];
        }
}

int Split(int l,int r)
{
    int x=Findkth(l);
    int y=Findkth(r+2);
    Splay(x,0); Splay(y,x);
    return Son[y][0];
}

int main()
{
	freopen("a.in","r",stdin);
	freopen("a.out","w",stdout);
    scanf("%d",&n);
    Build(0,1,n+2);
    Root=(n+3)>>1;
    for (int i=1; i<=n; ++i)
    {
        scanf("%d",&x); x%=n-i+1;
        if (x)
        {
            int now=Split(1,x);
			Son[Father[now]][Son[Father[now]][1]==now]=0;
            Father[now]=0;
            int fa=Split(n-i+1-x,n-i+1-x);
			Son[fa][1]=now; Father[now]=fa;
            Splay(now,0);
            
        }
        int now=Split(1,1); printf("%d\n",now-1);
        Son[Father[now]][0]=0;
        Father[now]=0; Update(Son[Root][1]);
    }
}