水題
#include <iostream> #include <set> #include <vector> #include <algorithm> using namespace std; int main(){ int n,v; cin >> n >> v; vector<int> res; for(int i = 0; i < n; ++ i){ int k,s; bool flag = false; cin >> k; for(int j =0 ; j < k; ++j){ int s; cin >> s; if(!flag && s < v) res.push_back(i+1),flag = true; } } cout<<res.size()<<endl; for(int i = 0 ; i < res.size(); ++ i){ if(i)cout<<" "; cout<<res[i]; } cout<<endl; }