代码：

#include<cstdio>
struct chocolate{
	int length,width;
}c[100010];
int n,k;
bool check(int x){
	int ans=0;
	for(int i=1;i<=n;i++)
		ans+=c[i].length/x*c[i].width/x;
	return ans>=k;
}
int Find(){
	int l=1,r=1e5,ans;
	while(l<=r){
		int mid=(l+r)/2;
		if(check(mid))ans=mid,l=mid+1;
		else r=mid-1;
	}return ans;
}
int main(){
	scanf("%d%d",&n,&k);
	for(int i=1;i<=n;i++)
		scanf("%d%d",&c[i].length,&c[i].width);
	printf("%d",Find());return 0;
}