hdu 4331 Image Recognition

wa的有点无语，细节比较多的题对我来说真伤不起。。。
#include<iostream>
#include<vector>
#include<string>
#include<cstdio>
#include<iomanip>
#include<algorithm>
using namespace std;
#define pb push_back
#define read            freopen("out.txt","r",stdin)
#define write           freopen("zz.txt","w",stdout)
const int maxn = 1005;

struct zz
{
    int now;
    bool w;
}zx;

vector<zz>g[maxn];
int a[maxn][maxn];
int u[maxn][maxn];
int d[maxn][maxn];
int r[maxn][maxn];
int l[maxn][maxn];
int x[maxn][maxn];
int fd[maxn];
int n;

int lowbit(int x)
{
    return x&(-x);
}

void insert(int x)
{
    while(x<maxn)
    {
        fd[x]++;
        x+=lowbit(x);
    }
    return ;
}

int find(int x)
{
    int temp = x - 1;
    int re=0;
    while(temp>0)
    {
        re+=fd[temp];
        temp-=lowbit(temp);
    }
    return re;
}

int start()
{
    int temp;
    int now;
    int tot;
    for(int k=2;k<=2*n;k++)
    {
        tot = 0;
        for(int i=0;i<=n;i++)
        {
            g[i].clear();
        }
        for(int i=1;i<=n;i++)
        {
            if(k-i<1 || k-i>n) continue;
            if(!a[i][k-i]) continue;
            temp = i-min(u[i][k-i],r[i][k-i]);
            zx.now = i;
            zx.w = false;
            g[temp].pb(zx);
            zx.w = true;
            temp = i;
            g[temp].pb(zx);
        }
        memset(fd,0,sizeof(fd));
        for(int i=1;i<=n;i++)
        {
            if(k-i<1 || k-i>n) continue;
            if(a[i][k-i])
            {
                temp = i+min(l[i][k-i],d[i][k-i])-1;
                insert(temp);
                tot++;
            }
            for(int j=0;j<g[i].size();j++)
            {
                if(g[i][j].w)
                {
                    now = g[i][j].now;
                    x[now][k-now]+=tot-find(now);
                }
                else
                {
                    now = g[i][j].now;
                    x[now][k-now]-=tot-find(now);
                }
            }
        }
    }
    int ans=0;
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=n;j++)
        {
            ans+=x[i][j];
        }
    }
    return ans;
}

int main()
{
    int T;
    cin>>T;
    for(int tt=1;tt<=T;tt++)
    {
        cin>>n;
        for(int i=1;i<=n;i++) for(int j=1;j<=n;j++)
        {
            scanf("%d",&a[i][j]);
            x[i][j]=u[i][j]=d[i][j]=r[i][j]=l[i][j]=0;
        }
        for(int i=1;i<=n;i++) for(int j=1;j<=n;j++)   if(a[i][j])

补充：软件开发 , C++ ,