编译错误~这是什么意思：

[Error] 'int' is not a class, struct, or union type

#include<cstdio>
#include<bits/stdc++.h>
#include<algorithm>
using namespace std;
struct z{
	int ls;
	int rs;
	int qs;
}c[20];
bool cmp(z &x,z &y)
{
	return x.qs>y.qs;
}
int main()
{
	//freopen("game.in","r",stdin);
	//freopen("game.out","w",stdout);
	int n;
	int a,b;
	int lc;
	cin>>n;
	cin>>a>>b;
	for(int i=0 ; i<n ; i++)
	{
		cin>>c[i].ls>>c[i].rs;
		lc=1;
		if(i==0)
		{
			c[i].qs=floor(a/c[i].rs);
		}
		else
		{
			for(int j=0 ; j<i ;j++)
			{
				lc=lc*c[j].ls;
			}
			lc=lc*a;
			c[i].qs=floor(lc/c[i].rs);
		}
	}
	sort(a,a+n,cmp);
	int ans;
	ans=floor(a/c[0].rs);
	cout<<ans;
	return 0;
}

谢谢了！！！