如题，打出了这样一份代码，但是无法通过编译，且错误信息很长。

#include <bits/stdc++.h>
using namespace std;

struct xiaofei
{
	int u,v;
}a[12];

bool cmp(xiaofei a,xiaofei b)
{
	if (a.u==b.u)
	{
		return a.v<b.v;
	}
	else
	{
		return a.u<b.u;
	}
}

int main()
{
	for (int i=1;i<=10;i++)
	{
		cin >> a[i].u >> a[i].v;
	}
	sort (a+1,a+11,cmp);
	int cnt=unique(a+1,a+11)-a-1;
	cout << cnt << endl;
	for (int i=1;i<=cnt;i++)
	{
		cout << a[i].u << " " << a[i].v << endl;
	}
	return 0;
}

谢谢！[爱心]