#include<iostream> (5488)#include<vector> #include<algorithm> using namespace std; int main() { long long n=0; cin>>n; vector<long long>a,b; for(int i=0;i<n;i++) { long long input; cin>>input; a.push_back(input); } for(int i=0;i<n;i++) { long long input; cin>>input; b.push_back(input); } sort(a.begin(),a.end()); sort(b.begin(),b.end()); vector<long long>possi; int j=0; for(int i=0;i<b.size();i++) { possi.push_back(0); for(j=i;j<a.size();j++) { if(b[i]>=a[j]) possi[possi.size()-1]=j+1; else break; } } long long ot=1; for(int i=0;i<possi.size();i++) { if(possi[i]==0) { ot=0; break; } else ot=ot*(possi[i]-i); } cout<<ot%100000007<<endl; return 0; } 第一题。。卡在哪里了啊